EU chief Donald Tusk has urged Theresa May to start Brexit negotiations ASAP as top politicians meet in Downing Street on Thursday morning.

The European Council president seems to be suggesting that the prime minister should trigger Article 50, the official mechanism to split from the EU, and start two years of talks with Brussels.

But the Conservative premier has already ruled out making such a move this year, while Brexit Secretary David Davis has hinted Article 50 will be triggered sometime in 2017.

Tusk’s and May’s meeting comes as the 27 other nations of the EU get together for an informal summit in Bratislava, Slovakia. The EU chief plans to update May on the talks.

May and Tusk meet outside Number 10 The Conservative premier told MPs this week that her government would not give a “running commentary” on its Brexit negotiations with the EU.

But her administration’s position on splitting from the political and economic remains unclear after Brexit Secretary David Davis was slapped down by Number 10 for saying it was “improbable” that the UK would remain in the single market because of May’s desire to implement tougher immigration rules.

On the immigration issue, May has rejected an Australian-style visa system, a programme backed by Foreign Secretary Boris Johnson and the Vote Leave campaign.

Amber Rudd, the new Home Secretary, has also revealed that the government will stick with David Cameron’s “tens of thousands” target.

The Conservatives have consistently failed to deliver on the general election commitment, with latest official figures putting net migration at 327,000 in the year to March 2016.

Rudd admitted to the Home Affairs Committee yesterday that it would “take some time” to meet the target.

Tusk and other EU chiefs have warned the UK cannot have ‘single market a la carte’, meaning that Britain cannot reject free movement of people and stay in the free-trade area.