Eurozone crisis: Leaders ready for 'do-or-die' summit
The talks have been described by analysts as "do-or-die" for the 17 eurozone nations.
Germany and France are pushing for new EU treaties, saying stricter fiscal rules should be enshrined there.
Meanwhile the European Central Bank is set to cut interest rates amid fears the eurozone is in recession.
European Commission chief Jose Manuel Barroso, who is in the French city of Marseille, has urged EU to "do everything" to save the euro ahead of the Brussels summit.
"The entire world is watching. We must do everything" to save the euro, he said, adding: "It is extremely important that we all together, all the EU, show that the euro is irreversible."
Mr Barroso is attending the annual congress of the centre-right grouping in the European Parliament, the European People's Party (EPP), in the southern French city, which French President Nicolas Sarkozy and German Chancellor Angela Merkel are also due to attend.
French Europe Minister Jean Leonetti has said the single currency and the EU itself could be under threat if leaders fail to tackle the debt crisis.
"The situation is serious - the euro can explode and Europe unravel," he told French TV.
"That can be a catastrophe not just for Europe and for France but for the world."
The 10 non-eurozone members of the 27-member EU, including the UK, are concerned they may become isolated if the eurozone nations - driven by Berlin and Paris - decide to move to a new treaty on their own; Kazinform cites BBC.
On Wednesday, US President Barack Obama discussed the eurozone crisis with Mrs Merkel during a telephone call. The White House said both leaders agreed that any solution had to be lasting and credible.
US Treasury Secretary Timothy Geithner has met new Italian Prime Minister Mario Monti in Rome to discuss ways of supporting the eurozone, and how international institutions like the IMF can assist the region "in this delicate phase", Mr Monti said in Rome.
To learn more go to www.bbc.co.uk
