David Cameron is heading for a crunch EU summit amid fears the continent is teetering on the brink of economic disaster.
There had been hopes the hastily-arranged gathering of leaders in Brussels would agree a deal to secure struggling eurozone members by shoring up banks and ramping up emergency funds.
But the prospects for decisive action appeared to be receding on Tuesday night. The cancellation of a meeting of finance ministers was taken as an indication that only broad outlines of a solution were being considered.
Meanwhile, Italian premier Silvio Berlusconi was fighting to get his coalition government to authorise new austerity measures being demanded in return for financial aid.
Frantic behind-the-scenes talks have been taking place in an effort to nail down three key issues that could soothe panicky markets.
A provisional agreement is already in place on the recapitalisation of Europe's most exposed banks - none in the UK - to the tune of about 100 billion euro (£87 billion). Many financial experts say at least half as much again will be needed to convince markets that they are well insulated against further economic shocks.
On the second plank, nothing is agreed on how to leverage an existing 440 billion euro (£383 billion) bailout fund to something above one trillion euros, to demonstrate a capacity to respond to any more Greek-style meltdowns.
And a decision is still awaited on a demand that private investors - mainly banks - absorb at least a 50% write-off of their loans to Greece.
Last weekend EU leaders set Wednesday as the absolute deadline for a deal, but the timetable has seemingly stretched as finance ministers will meet later this week.
UK officials have also suggested that a further summit of leaders could be required at the weekend to finalise the package.