The brewing crisis over Greece's debt and the country's future in the euro zone is expected to dominate talks at the latest G-20 summit in Istanbul Monday as the world's finance leaders expressed concern that Greece is on an unstoppable collision course with its international lenders.
The impasse between Greece and its lenders took a turn for the worse Sunday when the new Greek Prime Minister Alexis Tsipras vowed to push on with promises to roll back on austerity measures and stressed that his country would not be asking for an extension to its current bailout, which is due to end February 28.
On Monday, global finance leaders expressed concerns that the window of opportunity for a solution was closing.
U.S. Treasury secretary Jack Lew told CNBC on the sidelines on the G20 summit Monday that parties on both sides of the debate needed reel in the rhetoric.
"I think what has to happen right now is that everybody's got to tamp down the rhetoric a little bit," he told CNBC's Steve Liesman.
"There needs to be a conversation where Greece, and all of the parties that it's engaged with, look for a practical, pragmatic path forward-- which I think is in everybody's best interest."
The "troika" of international bodies overseeing Greece's bailout loans -- the European Central Bank (ECB), European Commission and International Monetary Fund – has said it won't release a last tranche of aid to Greece until the government makes a commitment to continue with the conditions of its bailout, including austerity. The ECB has also refused Greece's request for a bridging loan once its bailout ends later this month.
Nonetheless, finance chiefs were pushing for negotiations.
"I think there is still an opportunity for all sides to have a negotiation but I think (that is) narrowing pretty quickly so let's hope we can find a way through this," Timothy D. Adams, the president and chief executive of the Institute of International Finance, told CNBC on the sidelines on the G20 summit Monday.
"I think there is a way through this crisis but it requires cooler heads to prevail, (they need to) tone down the rhetoric and roll up their sleeves and get to work on a solution. I believe there is a solution but the rhetoric doesn't help."
Greece is likely to be the hot topic for finance ministers from the group of 20 nations (G-20) when they meet in Istanbul Monday and Tuesday to discuss the global economy and the political and economic stability of Europe as Greece plays hard ball over its bailout.
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Attempting to add weight to Greece's bargaining position, Greek Finance Minister Yanis Varoufakis said on Sunday that if Greece is forced out of the euro zone, other countries would inevitably follow and the currency bloc would collapse.
Angel Gurria, secretary general of the Organisation for Economic Co-operation and Development (OECD) told CNBC that he would do whatever he can to prevent Greece dramatically exiting the single currency union – a so-called "Grexit."
"Everybody wants Greece to stay in the European Union, everybody wants Greece to prosper and to get out of its short-term morass," he told CNBC Monday at the G20 summit, although he conceded there were political, regulatory and formal and legal restraints restricting what Greece and Europe could agree to, however.
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"I don't feel there's a chance of a Grexit but I will certainly do everything I can to avoid it because I don't feel it solves any fundamental problem and I don't it's good either for Europe or Greece."
The head of the OECD is due to visit Athens Tuesday following the G20 summit to speak to the new Greek government. Gurria said he would discuss the immediate financing situation in the Greek banking system and the servicing of its debt.
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