Following the British referendum to exit the European Union, UK citizens could pay to retain their EU citizenship under plans being considered by Members of the European Parliament (MEPs).

Guy Verhofstadt, the former Belgian prime minister and lead Brexit negotiator in the European Parliament, said he supported the principle of the idea, which would see Britons paying an annual fee to the EU.

"Many say 'we don't want to cut our links'," he told The Times. "I like the idea that people who are European citizens and saying they want to keep it have the possibility of doing so. As a principle I like it."

MEPs will vote on the proposal by the end of the year, but any Brexit agreement with Britain would also have to be approved by the leaders of the other 27 EU countries.

Immigration and trade are set to be the key issues in the looming Brexit negotiations. European leaders say they will maintain a tough stance during the negotiations.

The UK cannot expect a better relationship with the EU than it currently has once it leaves the bloc, incoming EU President Joseph Muscat said on Friday.

"There will not be a situation where the UK will have a better deal than it has today. It simply cannot be," Muscat, who is the Maltese prime minister, told BBC radio.

“This is really and truly our position and I don't see it changing," he said, dismissing any softening of the EU position in the Brexit talks.

The tiny Mediterranean island of Malta, a former British colony, takes over the EU's rotating six-month presidency in January.

British Prime Minister Theresa May has said she will trigger Article 50 of the EU treaty before the end of March next year. Article 50 is the two-year negotiation process for leaving the 28-nation bloc.

Last week, Dutch Finance Minister Jeroen Dijsselbloem accused British Foreign Secretary Boris Johnson of "saying things that are intellectually impossible, politically unavailable," referring to Johnson’s suggestion that post-Brexit Britain could have access to the EU's single market while restricting free movement of EU citizens.