Talks between Greece and its creditors need to "speed up", the EU's Economic and Financial Affairs Commissioner said Tuesday, as the Greek government warned that it was running out of money.
"We are aware of the liquidity problems in Greece and this is why it's so important now that negotiations that take place in Brussels speed up," Pierre Moscovici told reporters on the sidelines of a conference in Dublin.
"We want that agreement, we want it fast -- we are working on it hard," said Moscovici, a former French finance minister.
"It would be wrong to tell there is no progress on substance -- we are now discussing on concrete proposals," he said.
But he added: "We still have a way to go if we want an agreement".
The cash crunch has been caused by Greece's inability to agree with its creditors -- the International Monetary Fund, the European Union and the European Central Bank -- on reforms that would unlock 7.2 billion euros ($7.9 billion) in promised bailout cash.
"There is no plan B. There is a plan for a solid Greece remaining in the eurozone," Moscovici said on Tuesday.
"The exit of Greece would be a major problem. Of course if one country was to leave the eurozone then the nature of the euro would be damaged," he added.
Over the weekend, a cabinet minister said Greece had "no money" to make a series of repayments to the IMF from June 5 but a government spokesman insisted the country would keep up payments as long as it could.
Finance Minister Yanis Varoufakis said Tuesday that Greece's creditors must "get their act together" and help produce a new loan deal for the cash-strapped country.