Tusk is expected to rally Brown to support Poland's demands for eased financial terms for newer EU members related to the climate and energy package, Slawomir Nowak told Poland's PAP news agency on Thursday.

The global financial crisis is also expected to be on the agenda.

EU nations want to cut CO2 emissions by 20 percent by 2020 compared with 1990 levels.

Relying on CO2-spewing coal-fired plants for 94 percent of its electricity, Poland has threatened to veto the entire EU environmental package if a compromise on the cost of CO2 emission quotas is not found.

It and other coal-dependent eastern European EU members have opposed the bloc's original proposal to begin full auctioning of CO2 emission quotas for industry in 2013, arguing it would see energy prices skyrocket and economic growth nosedive.

Poland on Wednesday rejected an EU proposal that at least half of CO2 emission quotas be handed out free until 2016 for countries relying on coal for 60 percent of their electricity, a move aimed at averting a Polish veto of the bloc's climate package.

With France currently holding the EU's six-month rotating presidency, French President Nicolas Sarkozy is due to meet with Tusk and eight other east European leaders opposing costly emission quota auctioning.

Sarkozy is charged with clinching a deal by way of unanimous agreement of the bloc's 27 members on its proposed package combatting climate change at its December 11-12 summit.