The deal will see Greece promising to implement a package of austerity measures in exchange for €120bn loan to save the Greek economy.
The Greek prime minister George Papandreou is expected to announce details of the package tomorrow.
Earlier, anti-riot police fired tear gas at youths protesting in Athens, as a trade union march marking May Day passed in front of the finance ministry.
The demonstrations and strikes took place in protest at the austerity measures being demanded by the EU as the price for financially rescuing the Greek economy.
In the northern city of Thessaloniki, police also fired tear gas at youths who attacked banks and businesses with iron bars during a May Day protest.
EU and International Monetary Fund officials have been negotiating with the Greek government on unblocking crisis loans over the next three years worth €45bn in the first year.
The Greek government must agree to strict austerity measures, including slashing spending and raising taxes in return for the desperately needed loans.
Separately, German Chancellor Angela Merkel has said she would welcome a contribution from Germany's private sector to support a Greek rescue package.
'I would very much welcome the voluntary participation from banks,' Chancellor Merkel said, according to advance excerpts of the interview to appear on Sunday in Bild am Sonntag.
Deutsche Bank Chief Executive Josef Ackermann is helping coordinate German private sector efforts to support the rescue package, a senior banking source told Reuters on Friday.
The move would make it easier for political leaders to sell a bailout to the German public ahead of a key state election.
The consortium has already pledged to contribute between €1bn and €2bn toward the effort, although no formal agreement has been struck, the source said, declining to give details on how the plan would work.
