REUTERS/Yiorgos Karahalis
But there are already some indications that Germany is souring against Greece's membership of the eurozone entirely, even before discussions of really awkward trade-offs have started.
A poll by German broadcaster ZDF found that 52% of Germans think Greece should leave the eurozone, and only 40% think it should stay.
In February, the figures were reversed - with a 52% majority wanting Greece to stay.
Bloomberg spoke to ordinary Germans and academics after the poll, and it looks like the country's stance is harder than ever:
"The way the Greeks have been behaving has been impossible. Now they're making their own demands with these reparations," said Dorli Schneider, an interpreter waiting for a train at Munich's central station. "Greece should pay back what they owe. We can't forever give them more money."
German voters' growing umbrage may make it harder for Merkel to sell any possible deal down the road to the German public and Bundestag, which would have to vote on it. She also has to be wary of the anti-euro AfD party trying to peel off her voters, said Juergen Falter, a political scientist at the Johannes Gutenberg University in Mainz.
"The pressure is coming from two sides: the public and some opposition parties," he said. "The government will probably now react more decisively."
Since February, things have soured between the two countries. The new Greek government's defence minister, who comes from the right-wing and anti-austerity Independent Greeks party, has threatened to flood Europe with migrants if a debt deal isn't reached.
The Greek justice minister has threatened to sign a law which would let Greeks claim German assets as compensation for Nazi-era crimes.
And in Germany, Chancellor Angela Merkel reportedly avoided a much larger rebellion of her own party against extending Greece's current bailout.
These polls may even flatter current sentiment towards Greece. They came out before this weekend's latest drama, in which footage of Greek finance minister Yanis Varoufakis giving Germany the finger caused a furore.
Things are looking bleak, and they're only likely to get worse as the summer rolls in. The Greek government won't want to lose face in negotiations, but Germany already seems like it's giving as much as its population and politicians are willing to offer.