Greece leaving the eurozone would be a disaster both for the debt-laden country and the single currency, France's prime minister warned on Monday as European leaders continued to try and thrash out a deal on a new bailout for Athens.

Asked about the so-called "Grexit," Manuel Valls told French radio that he hoped the option was no longer under discussion at the marathon talks in Brussels. "Because that would be a disaster. A disaster first and foremost for the Greeks, who would live through an unprecedented social and economic shock, which will be even harsher than what they have lived through up to now... The consequences for the eurozone itself would be damaging because it would be weakened."