Theresa May will today discuss Brexit with European Council president Donald Tusk amid increasing pressure over a lack of detail in the Government's stated strategy.
The Prime Minister has faced accusations of vagueness and contradiction over the Government's position on remaining in the European single market, but has insisted she will not reveal her negotiating hand "prematurely".
The meeting comes after she slapped down Brexit Secretary David Davis for suggesting that continued membership of the free trade zone was "very improbable".
Mr Davis's comment appeared to play into the hands of EU countries who have insisted that Britain cannot have full control over its borders and remain a member of the single market.
Mrs May may use her working breakfast with Mr Tusk at No 10 to reaffirm her message that Mr Davis was expressing an opinion rather than Government policy, and that she continues to seek a bespoke model for the UK.
The talks will also touch on migration, trade and Ukraine, but observers will be keen to see if they yield any more details on Brexit.
The Prime Minister's official spokeswoman said: "It will be an opportunity in part to talk about the process of leaving the European Union, how we see the upcoming months, but also to talk about the upcoming October European Council and some of the issues that we expect to be on the agenda for that, such as migration, trade and where we are at with the situation in eastern Ukraine."
Mrs May on Wednesday told MPs she was seeking "the right deal" on trade in goods and services after Britain withdraws from the EU, but added: "We will not take decisions until we are ready, we will not reveal our hand prematurely and we will not provide a running commentary on every twist and turn of the negotiations."
She refused to say whether she wanted the UK to remain in the European single market.
The PM and her ministers were accused of "waffle" by Scottish National Party Westminster leader Angus Robertson, while the Liberal Democrats' Tim Farron said: "This Government isn't concealing its hand - it hasn't got a hand or, it would appear, a clue."
Jeremy Corbyn accused the Government of issuing "contradictory messages" on Brexit which were exacerbating "huge uncertainty" about the UK's future.
But the Labour leader found himself in a row over the single market after a senior aide suggested he might rule out full membership unless Britain can negotiate exemptions from key EU rules.
That prompted Mr Corbyn's team to stress that he backed "full access" to the single market for goods and services but opposed certain directives linked to it, such as state aid rules and requirements to deregulate and privatise public services.