The European Central Bank has approved a 68 billion euro ($78 billion), two-week extension on emergency liquidity for Greek banks, Reuters reported, citing a source.

The ECB had already raised the Emergency Liquidity Assistance (ELA) cap to about 65 billion euros last Thursday. The Greek central bank had requested an extension of about 10 billion euros, the source told Reuters.

The added assistance comes as Greece tries to negotiate a financing deal with European partners. The country on Thursday will request that the euro zone extend a "loan agreement'' for up to six months, though Germany has said that no such deal is on the table and Athens must abide by the terms of its existing international bailout.

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Greek Finance Minister Yanis Varoufakis told reporters separately on Wednesday that he believes euro zone finance ministers will approve the Greek proposal later this week, Reuters reported. Euro zone officials will first consider the Greek loan extension request in a working group on Thursday.