Greek prime minister George Papandreou said that "very important decisions" were taken at the EU summit in Brussels, speaking to reporters late Thursday after the conclusion of the first day of talks.

"We believe that we are on a very steady course, although a difficult one, with many sacrifices, that will lead us to a strong and viable economy. We received the support of our (EU) partners, and this is a positive development for Greece's future, and not simply a 'green light'," he added.

The EU heads of state and government on Thursday agreed the basic guidelines for new financial assistance to Greece that will meet the country's borrowing needs up to end-2014, and reiterated its preparedness to disburse the 12 billion euros 5th tranche of the 110 billion euro EU-IMF bailout loan in early July, on condition that the Greek government's Medium-Term fiscal programme and its Implementation Law are passed by parliament by June 30.

The Medium-Term Fiscal Strategy Program is slated for vote in the 300-seat unicameral parliament on Tuesday, June 28, after a two-day debate, followed immediately by the Implementation Law.

The EU leaders also agreed a draft statement of Conclusions, to be finalised on Friday, which contains lengthy reference to Greece, which acknowledges the "considerable progress" achieved in the last year and gave the go-ahead for a second assistance program covering up to the end of 2014.