Further talks are due in Greece amid a scramble to try to secure a workable government following inconclusive elections nine days ago.
Leftist parties have signaled their opposition to joining a coalition that would stick to unpopular austerity policies in exchange for bailouts.The president has proposed a government of technocrats, but party leaders are pessimistic any deal can be reached.
The political turmoil has spooked markets around the world.
Heavy losses in Europe and the US on Monday were followed by falls in Asia on Tuesday morning.
If the cliff-edge talks fail, Greece will face fresh elections, prolonged political instability and possibly a slide towards an exit from the euro.
The stakes could not be higher. If Greece leaves the euro, the whole ideological framework governing monetary union could begin to unravel.
Such a scenario was rejected as "nonsense" by the chairman of the euro zone group, Luxembourg Prime Minister Jean-Claude Juncker, on Monday - but commentators say the fact that it is being openly discussed means a taboo has been broken in Brussels. The tumbling euro means other countries risk spiraling into further crisis. Borrowing costs in Spain are nearing dangerous levels, correspondents point out.Greece's wait goes on. One proposal under discussion is that of the president to form a government of technocrats, made up of what are described as "distinguished and non-political figures".
That has received a mixed reaction from some parties, aware that many Greeks resent the country's outgoing prime minister for being an appointed technocrat rather than an elected leader. But the politicians appear too divided to serve together in a coalition - split over whether to adhere to or reject Greece's bailout agreement and further cost-cutting.
If these last-ditch talks fail, Greece will face fresh elections, prolonged political instability and possibly a slide towards an exit from the euro. Greece's president appears determined to try everything he can to avoid it.
Norwegian
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