As for solidarity, adoption of the fiscal compact is her condition for granting new bail-outs under the permanent euro-zone rescue fund coming into effect this year.
He also wants to increase the size of the European Stability Mechanism, the zone's permanent bailout fund which will be up and running later this year.
It was also agreed that the European Stability Mechanism (the zone's permanent bailout fund that will start operating in July) could buy government bonds and drive down a country's borrowing costs.