Greek PM Alexis Tsipras has threatened to resign over the result of a snap referendum on Greece’s debt crisis due on Sunday.
Mr Tsipras said a clear vote against austerity would help Greece negotiate a better settlement to the crisis.
Otherwise, he warned, he would not stay in office to oversee more cuts.
Greece’s bailout expires on Tuesday, the same day it faces a deadline to repay a €1.6bn (£1.1bn) loan to the International Monetary Fund (IMF).
The loan is to be repaid by 18:00 Washington time (22:00 GMT).
As the deadline nears, reports in Greece say a last-minute offer was made by creditors on Monday night.
EU leaders have warned that a rejection of the creditors’ proposals on Sunday would mean Greece leaving the eurozone – though Mr Tsipras says he does not want this to happen.
Talks between Greece and its creditors broke down last week, leading to Greek banks having to shut this week.