Fish for finance is a possible trade-off that has been considered by both sides in the trade negotiations between the United Kingdom and the European Union (EU) over their future relationship following Brexit in January 2020. The Brexit withdrawal agreement between the two parties called for an agreement on fisheries to be concluded by June 2020, followed by an agreement on financial services at the end of July, deadlines which were both missed. Both were expected to be part of the final EU–UK trade agreement reached by the end of 2020, the end of the Brexit transition period. The final agreement had some broad outlines for a future fishing deal, primarily gradual EU concessions of fishing quota in UK waters, but was largely silent on finance.

British commercial fishermen were among the most ardent supporters of Brexit before and after the 2016 referendum that began the process when a majority of voters opted for the country to leave the EU. Many of them had expressed discontent with the EU's Common Fisheries Policy (CFP), under which the UK has had to share its exclusive economic zone (EEZ) with other member states' fishing fleets; Brexit proponents have argued that British fishermen should be able to catch at least the majority of the fish in that portion of the country's EEZ around the island of Great Britain and off the coast of Northern Ireland. During the UK's membership in the EU, much of the fish that British fishermen have historically caught in the EEZ has been exported to mainland Europe, leading many British fish processors, fish farmers and inshore fishermen (whose catch of primarily shellfish is popular with consumers in France and Spain, but not the UK) to seek a continuation of the pre-2021 frictionless trade situation; conversely a majority of the fish consumed in the UK is caught outside British waters. It was feared that EU fishermen, who had themselves historically fished British waters, planned to block imports of British fish, and even all British imports, if the UK limited their rights to do so. Industry advocates on both sides feared this would lead to potentially lethal violence on sea and land, in addition to the economic consequences of a trade war. The EU's eight western coastal states, whose fleets partake of the catch in British waters, asked that no overall trade deal with the UK be concluded without a fisheries agreement; the UK conversely believed the issue does not have to be settled first.

The British financial sector, which employs more people and accounts for a much greater share of the country's gross domestic product (GDP) than fishing, made clear that it would like at the very least a declaration of stock market equivalence similar to what the EU has extended to the US, Hong Kong, Australia and (in the past) Switzerland. Ideally the City wishes to maintain the level of access to EU markets it has enjoyed during the UK's membership in the bloc. EU officials and negotiators have said that they would be inclined to continue allowing that level of access only if the UK is likewise willing to allow the same level of access to its fisheries. Unlike the UK's fishermen, financial companies can move to take advantage of more favourable regulatory climates, and many have already begun relocating staff and operations to Dublin, Frankfurt, Paris or Amsterdam, or elsewhere in the EU.

Deadlines set originally by the Withdrawal Agreement were missed, in part due to the disruption caused by the COVID-19 pandemic. By the end of 2020, it did not appear to observers or the parties themselves as if a deal would be reached, and the UK and EU both began to prepare for the worst possible impacts of that transition. On 24 December, a deal was announced with a compromise on fishing quotas which UK fishing industry spokesmen found disappointing. Negotiations continue on a substantial financial services agreement, despite missing the original deadline of 31 March 2020.

Planned negotiation timetable

The Withdrawal Agreement by which the UK left the European Union at the end of January 2020 included a non-binding political declaration, concluded the previous October, setting the terms for post-Brexit relations, with the intent of reaching a comprehensive trade agreement by the end of 2020. The declaration sets forth specific dates prior to that for negotiating agreements on particular economic sectors. Among them are fisheries and financial services.

On fishing, the declaration calls for the two parties to 'use their best endeavours to conclude and ratify their new fisheries agreement by 1 July 2020 in order for it to be in place in time to be used for determining fishing opportunities for the first year after the transition period'. No similar deadline is established for an agreement on financial services. Instead, the two sides committed to assessing each other's regulatory frameworks for stock market equivalence by the end of June.

Before that date, the agreement called for both sides to have a summit conference to assess the progress of the talks. Should the British government have desired an extension of the transition period to allow for longer negotiations, it could have requested one of up to two years no later than 1 July; the EU would have had to agree. These terms are set by the Withdrawal Agreement; to modify them would require a formal modification to that agreement itself.

For the government to have requested an extension, it would also have to get permission from Parliament. An amendment to the bill implementing Brexit, barred the government from requesting one. Prime Minister Boris Johnson further told Parliament he would not request one, arguing that for trade talks to produce timely results, there needs to be a clear and early deadline.

None of these deadlines were met; the disruptions resulting from the COVID-19 pandemic, which required several rounds of talks to be held virtually, have been held to blame, but the two sides remain very far apart in on the issues. Negotiations on fisheries continue with little indication of progress. By 30 June, the UK had only completed and returned four of the 28 questionnaires about its securities market regulation sent it by the EU; three weeks later, the government reported that all had been completed and returned. At that same time, the government confirmed it would not be seeking an extension, committing the UK to fully leaving the EU at the end of the year no matter what the circumstances.

Fishing and the United Kingdom

History of fishing conflicts and agreements between the UK and other nations

Seafood has long been a staple of inhabitants of the British Isles, surrounded by one of the world's richest fisheries. Danish and Norse raiders in the ninth century brought one fish species in particular, the North Sea cod, into the national diet. Other whitefish like halibut, hake and pollock, also became popular.

By the end of the 14th century, fishing boats from the east coast of England, then as now home to most of the English fishing fleet, were sailing to Icelandic waters in search of these catches; their landings grew so abundant as to cause political friction between England and Denmark, who ruled Iceland at the time. The Danish King Eric banned all Icelandic trade with England in 1414 and complained to his English counterpart, Henry V, about the depletion of fishing stocks off the island. Restrictions on British fishing passed by Parliament were generally ignored and unenforced, leading to violence and the Anglo-Hanseatic War (1469–74). Diplomats resolved these disputes through agreements that allowed British ships to fish Icelandic waters with seven-year licences, a provision that was struck from the Treaty of Utrecht when it was presented to the Icelandic Althing for ratification in 1474. This started a centuries-long series of intermittent disputes between the two countries, the most recent of which were the three "Cod Wars" between 1958 and 1976.

Fishermen in Scotland, a country more dependent on their industry than England, bitterly resented the competition from Dutch boats in the country's waters, and when their king James united the Scottish and English crowns in 1609 as James I he reversed what had been the tolerant policies of his Tudor predecessors toward foreign fishing in British coastal waters and began requiring a steep licence fee. Dutch legal scholar Hugo Grotius had at the same time argued, in response to clashes between his country and Portugal, for the mare liberum principle, under which the seas were common property and all nations and people had a right to use it as they chose. England's John Selden responded in 1635 with the mare clausum "closed sea" principle under which a nation could appropriate the seas as easily as it would land.

During the 18th century, British governments complained to France and the Netherlands as well as Denmark about their countries' fishing boats venturing into British waters. Eventually the Dutch agreed to respect a six-mile () limit, going no closer to British shores. After the Napoleonic Wars, French fishermen became much more aggressive around Great Britain, making their presence known along the Scottish coast and in the English Channel; the complaints they generated from British fishermen were reciprocated against them by the French. In 1843 the two countries concluded the first ever international agreement establishing exclusivity zones for their fisheries, of three miles (4.8 km) from their respective shores.

Domestic demand for seafood in the UK grew rapidly following the Industrial Revolution, as the development of the country's rail network allowed fresh fish to reach a wider market away from the coasts; fish and chips, first served in the 1860s, generally made with either cod or haddock, quickly grew to become a staple of English cuisine and a national symbol. In response, steam-powered trawlers, which could go farther, stay out longer and catch more fish than their sail-driven predecessors, were added to the fishing fleet. This development has been considered the beginning of the decline of the British fishing industry, since even though its fish landings continued to increase until the late 1930s, when they were more than five times those of the late 2010s, the fleet's productivity, measured in fish landings per unit of fishing power (LPUP), began a steady decline that continues.

In the early 20th century, the return of modern British fishing boats to inshore waters off the northern coast of Norway after almost three centuries when they had respected royal decrees barring them from those areas, provoked a local backlash, and the newly independent Norwegian government began specifying conditions under which foreign boats could fish the country's waters north of the Arctic Circle. The seizure of a British trawler for violating those laws started negotiations between the two governments that World War I interrupted; afterwards the incidents continued, resulting in a 1935 Norwegian royal decree claiming the waters within of its shoreline as exclusively Norwegian, but enforcing it only irregularly pending an agreement with the UK. Thirteen years later, no agreement had been reached and after Norway began strictly enforcing its limit, the UK brought suit at the International Court of Justice, arguing that Norway's limits did not follow its coastline in that area as strictly as international law required. In 1951 the court found in Norway's favour.