The European Union has canceled a full 28-nation summit on Greece's bailout hopes Sunday, and will instead limit the talks to leaders of the eurozone nations.
The 19 eurozone finance ministers are continuing to meet in Brussels, after eight hours of talks Saturday failed to produce a breakthrough.
The ministers' meeting will "last until we conclude talks on Greece," said European Council President Donald Tusk.
Eurozone officials are grappling with Greece's failure to meet a repayment deadline on a loan installment earlier this month. They are also seeking additional assurances that Athens will honor terms of any new deal.
Sources say the finance ministers used their Saturday meeting to formulate demands for additional Greek budget and political reforms before they open negotiations on any new loans.