ATHENS, Greece – The International Monetary Fund on Thursday approved $36.56 billion in funding for crisis-hit Greece over the next four years, while Standard and Poor’s said the country’s new bonds were still vulnerable to a default.

IMF’s executive board granted the immediate release of $2.15 billion of these funds as part of the country’s second bailout, a statement said.

Greece will receive a total 172.7 billion euros in rescue loans from its eurozone partners and the IMF to keep it afloat in the next few years, as dizzily high borrowing rates have blocked its ability to raise money on the international bond markets.

IMF Managing Director Christine Lagarde warned that risks to Greece’s austerity and reform program still “remain exceptionally high, and there is no room for slippages.”

Lagarde said new pain lies ahead for Greeks, despite the tough measures implemented over the past two years.

“Full and timely implementation of the planned adjustment — alongside broad-based public support and support from Greece’s European partners — will be critical to success,” she said.

“Significant further fiscal adjustment is necessary to put debt on a sustainable downward trajectory,” Lagarde said, adding that politically difficult spending cuts lie ahead.

Without the bailout, Greece would have been forced into a messy default.

Also Thursday, Finance Minister Evangelos Venizelos said he would ensure the terms of the bailout deals would be met if he is part of the next government.

Venizelos is the only contender for the leadership of the majority socialist PASOK party in a vote this Sunday. Once he takes over the party helm, he will resign as minister to focus on the election campaign.

“It is hypocritical to say that you can sign commitments and then say you are not bound by them. That’s an insult to our intelligence,” Venizelos said.