Angela Merkel and Francois Hollande are expected to tell Greek Prime Minister Antonis Samaras this week that they can give him little leeway on easing the terms of his country's bailout agreement.
The French and German leaders meet today to fine-tune their joint message to Samaras, who is on a charm offensive seeking more time for Athens to meet its bailout commitments.
Senior German coalition leaders have signalled there is little chance of that and Merkel herself poured cold water on far-reaching concessions on Wednesday.
"I am going into these talks with the awareness that we have to achieve that every partner sticks to his commitments," Merkel said.
The chancellor may also lean on France's new Socialist leader to set an example to the euro zone by applying some austerity himself in France's 2013 budget debate next month.
Merkel receives Samaras on Friday and Hollande receives him on Saturday, at a moment of rare optimism on financial markets that the European Union – especially the European Central Bank – is poised for decisive action on the euro zone debt crisis.