Greece agreed to start urgent technical talks on extending its crucial bailout on Wednesday after its eurozone partners accused debt-stricken Athens of wasting time in previous negotiations.
The main talks will be in Brussels but teams from Greece's creditors will also be on the ground in Athens, Eurogroup chief Jeroen Dijsselbloem said, despite the new left-wing government's earlier insistence that they should not return.
The announcement came after a meeting of eurozone finance ministers in Brussels on Monday at which the Greek government outlined the reforms demanded by lenders in exchange for further cash.
The ministers agreed last month to extend Greece's current bailout until June as long as Athens comes up with suitable proposals, but Dijsselbloem accused the Greeks of wasting time.
"We have spent two weeks discussing who meets who where and in what format, and it's a complete waste of time," Dijsselbloem, who is also Dutch finance minister, told a press conference after the meeting.
"We agreed today that there is no further time to lose. Discussions between the Greek government and the institutions will start on Wednesday in Brussels... in parallel, technical teams from the institutions will be welcomed in Athens."
Greece's new Prime Minister Alexis Tsipras had previously vowed that the "institutions" -- formerly known as the widely loathed "troika" of the EU, European Central Bank and International Monetary Fund -- should not return to Athens.
Greek Finance Minister Yanis Varoufakis insisted that Athens had not wasted any time and was looking forward to the start of the technical talks on Wednesday.
As for the troika going to Athens, of that there could be no question, Varoufakis told reporters.
But Greece was a member in its own right of the EU, the ECB and the IMF and as a "welcoming country... we will be welcoming all members of the institutions to Greece to do some very serious work," he added.
- Greece 'positive' -
The Greek government said the result of Monday's talks was "positive" and noted a "willingness to resolve (Greece's) financial problem rapidly".
The euro dived to an 11-and-a-half-year low against the dollar as fears grew over Greece's future and Europe's main stock markets closed mostly lower, despite the European Central Bank's launch Monday of its 1.1 trillion euro ($1.2 trillion) economic stimulus programme for the eurozone.
The thorny question of a likely third bailout to tackle debts that amount to around 175 percent of Greece's annual economic output did not appear to feature at the talks in Brussels.
Tsipras vowed on his election in January to renegotiate Greece's debts and end austerity measures imposed under two bailouts worth 240 billion euros since 2010, although Athens has since backed down on several points.
It won an extension of its current bailout until June but the payout of the next tranche of some seven billion euros at the end of April is dependent on a review of the reform plans, meaning that Athens is rapidly running out of time.
Dijsselbloem warned Greece that it would not get any payments until there was a full agreement and implementation of the reforms.
"There cannot be disbursement... if we do not have implementation," he said.
- Referendum warning -
Varoufakis, the tie-eschewing former professor whose hard-charging style has irritated several of his counterparts, sent a letter with seven main reforms to the Eurogroup on Friday.
They included a much derided proposal to have tourists pose as amateur sleuths to crack down on tax dodgers, as well as proposals to streamline the country's notorious bureaucracy and raise revenue from online gambling, while savings would be used to help the poorest.
German Finance Minister Wolfgang Schaeuble said Athens -- which has long been at odds with Europe's most powerful economy over the austerity measures included in the bailout conditions -- should avoid "unilateral" changes.
With speculation mounting about a chaotic Greek exit from the euro, Varoufakis had fuelled uncertainty at the weekend about a possible referendum if the reform plans were rejected by Brussels.
"We can go back to elections. Call a referendum," Varoufakis warned in an interview with Italian newspaper Corriere della Sera on Sunday.
Varoufakis later said his comments had been taken out of context but they carried an unwelcome echo of November 2011 when then prime minister George Papandreou baulked at the terms of its second bailout and threatened to call a referendum.
The move infuriated Greece's European partners, spooked global markets and led to Papandreou's fall.
It was announced earlier Monday that Tsipras will meet European Commission chief Jean-Claude Juncker, the head of the EU's powerful executive arm, in Brussels on Friday.