European leaders could be set for a bout of indigestion later Thursday as they meet in Brussels to discuss over dinner the U.K.'s demands that the European Union reforms or risks losing a key member.
U.K. Prime Minister David Cameron will be attending the dinner in Brussels with other European heads of state and government, including the German Chancellor Angela Merkel and French President Francois Hollande, to try to break an impasse with EU leaders over the country's demands for reforms in the bloc.
President of the European Council Donald Tusk said there would be "no taboos" in the talks – but no promises on a deal either.
The discussions are expected to focus on U.K. plans for a referendum on EU membership by the end of 2017 and there are hopes that "some kind" of preliminary agreement on keeping Britain in a reformed EU.
The meeting, which kicks of a two-day summit of the European Council, will be chaired by Tusk, who wrote earlier this week that talks would aim "to see if we can pave the way for an agreement in February."
"During dinner we will discuss the U.K. issue, to see if we can pave the way for an agreement in February. As I set out in my letter, we have achieved significant progress in negotiations; however we are still far from an agreement on several topics," he said in a statement released earlier this week by the Council.
"This Thursday we will need to focus especially on the most controversial ones. The stakes are so high that we cannot escape a serious debate with no taboos," he warned.
The U.K.'s referendum on whether to stay in the EU or leave (a so-called "Brexit") could happen as soon as mid-2016. Ahead of the vote, the country's prime minister is trying to extract promises for reforms in Europe and to renegotiate the U.K.'s membership of the 28-member Union.
A spokeswoman for Cameron said the discussion among leaders on Thursday and Friday was "an important milestone in the United Kingdom renegotiating its membership," Reuters reported. The Conservative party's press office would not comment further ahead of the talks when contacted by CNBC.
The U.K. has already set out its formal demands in a letter to Tusk in November, when Cameron set out a four-pillared demands over economic governance (to ensure the protection of the single market for the U.K. and other non-euro countries), plans to boost competitiveness, sovereignty (allowing Britain to be exempt from the EU's objective of "ever-closer union") and crucially, immigration and restricting EU migrants' access to in-work benefits in the U.K.
The freedom of movement in the Union is a thorny issue between the U.K and Cameron has faced major opposition from Brussels over his desire to block EU migrants from claiming in-work benefits for a period of four years.
Migration is a hot political potato for Cameron, as well as other EU leaders, as anti-immigration sentiment is on the rise. Many members of the European public fear rising numbers of immigrants amid an influx of thousands of migrants fleeing civil war and poverty in the Middle East and Africa.
A poll of 20,000 voters showed that 47 percent of the public want to leave the EU, with 38 percent opting to remain and 14 percent undecided, according to a Lord Ashcroft poll published on Wednesday.
Just as many want to welcome the migrants in their hour of need, however and Germany has called for every country to "do their bit." EU leaders are also expected to discuss the migration issue when they meet this evening, as well as the president's report on the Economic and Monetary Union and the completion of the single market.