Greek Prime Minister Lucas Papademos and leaders of the three parties supporting his coalition government reiterated on Sunday "full consensus" to reforms amid difficult talks with international creditors to avert a devastating Greek bankruptcy within the eurozone.

Ahead of a new crucial European Union(EU) summit in Brussels on Monday, Papademos chaired a meeting of party leaders over the fresh demands of EU and International Monetary Fund (IMF) lenders to unlock further bailout aid to Athens and the progress on talks for a voluntary debt restructuring program with private sector bondholders.

"If this double process will not end successfully, we will face the prospect of a bankruptcy that will have great impact on society," warned the prime minister in a statement issued after the meeting.

Without further EU/IMF loans this winter and a deal to make the Greek sovereign debt sustainable, Greece could financially collapse in March.

Greece depends on international loans since 2010 to escape default in exchange of a plan to exit the crisis, but missed targets have increased pressure for more harsh policies.

Papademos stressed that there is a clear and absolute consensus among socialist PASOK leader George Papandreou, conservative New Democracy President Antonis Samaras and Popular Orthodox Rally (LAOS) head George Karatzaferi on the stance Greece must hold towards negotiations and the additional measures need to be taken to stave off the financial meltdown.

"The unity of the political forces and commitment to the necessary changes is a fundamental factor of credibility that strengthens the effectiveness of our financial policy and allows us to negotiate on better terms," he underlined, concluding that united Greeks can secure the country's position within Europe and the eurozone.

The interim government was formed in November to push through a deal with international creditors on the Private Sector Involvement (PSI) to efforts to address the Greek crisis through a write-down of part of the Greek debt in parallel with an austerity and reform drive to secure a second rescue package.

But, as negotiations dragged on and labor unions opened a new wave of strikes and protests over changes, some of the measures requested by lenders, such as a further decrease in labor costs in the private sector and new cuts on pensions, were met with strong reactions by coalition partners.

A negative vote by some lawmakers last week on a health reform as part of an omnibus bill last week, for instance, fuelled fear that the administration will face hard times pushing through the parliament more painful policies in the near future, as well as scenarios of an imminent cabinet reshuffle before snap general elections.

On Sunday, Papademos and coalition parties reassured that there is a strong united front to tackle the challenges ahead.