World Bulletin / News Desk 

Greece's government can make no more concessions in negotiations for a cash-for-reforms deal and its international lenders must take responsibility for their role in the talks, Labour Minister Panos Skourletis said on Tuesday.

Athens and its creditors from Europe and the International Monetary Fund are racing to prevent the country from defaulting on its debt and potentially leaving the euro zone.

The bloc has set a deadline of Friday to conclude the talks to allow time for institutions and ministers to approve a deal and secure parliamentary backing to disburse frozen aid before Greece's bailout expires at the end of June.

"There is no room for more compromises. We are waiting for the other side to assume its responsibilities," Skourletis told Greece's Skai TV, adding it was now time for a "political" solution to the crisis.

An EU official said any offer from Greece's creditors to Athens would not be framed as an ultimatum.

Asked if Athens would accept a "take it or leave it" deal, Nikos Filis, the parliamentary spokesman of Prime Minister Alexis Tsipras's ruling Syriza party, reiterated that the government could not sign an agreement that was incompatible with its anti-austerity programme.

"If we're talking about an ultimatum... which is not within the framework of the popular mandate, it is obvious that the government cannot co-sign and accept it," Filis told Antenna TV.