Poland`s coal-fired power stations would be temporarily exempted from buying all their greenhouse gas permits under a deal aimed to stop Warsaw vetoing the EU`s environmental plans, a source said Wednesday.

`The idea is to allow at least half of the CO2 emissions allowances to be handed out free, up to 2016, for countries where 60 percent or more of the electricity comes from coal-powered power stations,` one negotiator told AFP.

The finer details of the deal, which the French EU presidency has already put broadly to Warsaw, are still being hammered out, he added.

In its bid to tackle climate change, the 27 EU nations have committed to cutting greenhouse gases by 20 percent by 2020 compared with 1990 levels.

To achieve this, the European Commission proposes that European industry buys tradable permits to pollute from 2O13 via an auction system.

Poland and other eastern European EU members who still rely heavily on coal-powered energy plants have opposed the move, arguing that it would hit their economic growth.

The Polish government has threatened to veto the whole EU environmental package if a compromise is not found.

`We want to build an energy-climate package with which poorer EU states can survive,` Poland`s Prime Minister Donald Tusk told an EU summit in Brussels last month.

French President Nicolas Sarkozy will discuss the new proposal at a meeting with Tusk and counterparts from eight other eastern nations at a meeting on December 6 in Gdansk, cradle of Poland`s Solidarity trade union.

`It`s very different from what the Poles have been calling for but it is an opening gambit for negotiations with Warsaw,` a French EU presidency representative said.

Poland has raised several alternative proposals, including a guaranteed price corridor for future increases in energy prices, a so-called CO2-specific benchmarking-auctioning system and including gross domestic product in calculations for CO2 emission quota costs.

The CO2-specific benchmarking-auctioning system would reward electricity producers using the newest technologies -- emitting the least amount of carbon dioxide -- with free emission quotas.

Warsaw has been assured that the overall EU environmental action plan will only be decided at the highest level and unanimously -- hopefully at the next EU summit in Brussels on December 11-12.