Britain's future in the European Union will come under renewed scrutiny when David Cameron is grilled on the impact of the eurozone crisis by a panel of senior MPs.
The Prime Minister, who yesterday indicated that UK voters could be offered a referendum on whether to quit the EU, is due to make his regular appearance before the Liaison Committee.
His evidence comes amid sustained Tory backbench pressure for an immediate in/out poll in a stand-off that risks inflaming tensions with Liberal Democrat coalition partners.
Cameron rejected the calls for a quick vote, insisting that "over time" he hopes to secure a fresh deal with Brussels that would attract public assent.
While the status quo in Europe was "unacceptable", Cameron said in a Commons statement on last week's EU summit, leaving the Union altogether was not in Britain's best interests.
But asked by Tory MP Julian Lewis whether he was ruling out offering the public a chance to vote for that option, Mr Cameron replied: "That is not what I've said."
"I believe we should show strategic and tactical patience in this and then what I want to see is a fresh settlement that we seek fresh consent for," he said.
"The right time to determine questions about referendums and the rest of it is after we have that fresh settlement. That is what we should do."
Tory MP Conor Burns - who reportedly wrote to the prime minister last week urging Cameron to outline in terms the details of an in/out vote - said the public was "heartily sick of broken promises on referendums," and suggested tabling one would strengthen the PM's negotiating hand when dealing with other European leaders.
Mr Cameron agreed there was "some merit" in the call, backed by almost 100 Tory MPs in a letter, for a commitment to an EU referendum after the next general election to be enshrined in law.
But he said events were moving so fast in Europe, it would be difficult to predict what shape that referendum should take.
Labour accused the premier of a "nudge-nudge, wink-wink" policy that had nothing to do with the national interest and everything to do with managing dissent in the Tory ranks.
And a spokesman for Lib Dem Deputy Prime Minister Nick Clegg stressed that Mr Cameron was not stating agreed Government policy but "setting out his views as Conservative Party leader".
The Liaison Committee, made up of the chairs of the parliamentary select committees, has also placed civil service reform on the agenda for its 90-minute session with the Prime Minister.
A blueprint for a Whitehall shake-up was unveiled by Cabinet Office Minister Francis Maude last month - including tougher action against the worst-performing civil servants.
It also includes measures designed to improve accountability on big projects and to share services across departments as the service adapts to significantly lower staff numbers.
There is also to be a review of civil service terms and conditions to identify those "beyond what a good, modern employer would provide".