The prime ministers also criticised the response of some EU member states to the migrant crisis, with Mr Tsipras saying that the use of teargas and plastic bullets by Macedonian police during clashes with refugees at the Idomeni makeshift camp was a disgrace to European civilisation.

The Portuguese prime minister is in Athens on an official visit.

Speaking after his meeting with Mr Costa, the Greek prime minister slammed the role of the International Monetary Fund in Greece’s bail-out talks.

"In Greece wrong policies were applied and it is a paradox that those who recognized that there were wrong policies, admitting their mistake, insist on applying the mistake," said Mr Tsipras.

Greece is aiming for an agreement with its creditors on the next tranche of emergency loans by the beginning of May. The European Union, the European Central Bank and the IMF have been holding talks with government officials in Athens for the past week to discuss policy measures attached to the country’s bailout.

Debt talks

The biggest area of contention is the management of bad loans burdening bank balance sheets, Greece's minister of state Nikos Pappas said, with their positions closer on a pension system overhaul and income tax reform.

“We’ll find a solution in the coming weeks,” Germany's finance minister Wolfgang Schaeuble said in an interview with German public television channel ARD. This solution “has nothing to do with debt forgiveness, but with the fact that Greece needs to do more” to return to a competitive economy, he said.