Germany and France have insisted that any payment of financial aid to help Greece out of its huge debt problems must depend on the Greek authorities carrying out big spending cuts.
German Finance Minister Wolfgang Schauble says Greece must agree to strict new austerity measures.
A similar warning has come from the French government.
Earlier, the head of the International Monetary Fund, Dominique Strauss-Kahn, said Greece has nothing to fear from his organisation.
Greece has asked for a bailout by the IMF and the European Union.