* Wedded to coal energy, Poland balks at draft EU climate law
* Latest tiff between eurosceptic Warsaw, Brussels regulators
* Polish resistance on climate isolates it within EU
By Alissa de Carbonnel
BRUSSELS, Feb 5 (Reuters) - Poland is threatening to challenge a draft European Union climate law in court, EU documents seen by Reuters show, in its latest move to slow an EU campaign against global warming that Warsaw sees as a menace to its coal-powered energy industry.
In what Polish diplomats describe as leverage for talks now under way on how to spread the burden of EU climate goals among member states, Warsaw is opposing the legal basis for the rules - a battle it could take to the European Court of Justice (ECJ).
It puts Poland at odds with the rest of the 28-nation bloc, deepening fears in Brussels for the EU's ability to take the lead if U.S. President Donald Trump rows back, as he has warned, from global diplomacy to tackle climate change.
The EU's climate talks aim to strike a burden-sharing deal to uphold its pledge made as part of the global climate change deal reached in 2015 in Paris to slash greenhouse gas emissions by at least 40 percent below 1990 levels by 2030.
Climate rules touch a raw nerve in Poland, however: Over 80 percent of its energy comes from high-polluting, coal-fired plants and the conservative Law and Justice (PiS) party, elected in 2015, campaigned on a pledge to defend the coal industry.
Warsaw's opposition to EU climate goals is driven by a wider anger on the part of the eurosceptic government at EU complaints that its policies are eroding Polish democracy, including steps to limit the independence of the judiciary and media.
"But to challenge the legal basis (of EU climate policy) is extreme even for Poland," one EU official told Reuters.
An EU document seen by Reuters, in which Poland outlines its position for other member states, takes issue with the "legal basis and global context" of the climate change draft.
Warsaw proposes to strike from the title and preamble to the draft any mention that it aims to fulfil the EU commitment to the Paris Agreement, saying the wording is "too far-reaching" and raises doubt about the voluntary nature of the global pact.
It also cites an article in EU treaties that says rules on a nation's "choice between different energy sources" can only be adopted with the unanimous consent of the bloc's 28 nations, which would bypass the EU's environmentally-minded parliament.
Polish diplomats pushed to append this same wording to the EU's ratification of the December 2015 Paris accord to curb greenhouse gases.
"We were the troublemakers there, no doubt," a Polish diplomat said, adding that its new protest was only an opening gambit in the early stages of negotiations.
A spokeswoman for the European Commission said it was confident of the legal grounding for its climate change bill.
"It's a bluff (by Poland)," said another EU official, though adding that the EU executive was still concerned it may cause market uncertainty. "The minute they get what they want, they'll drop it. For them, it's an issue of national pride."
There is precedent suggesting Poland's action is serious: It has separately sued at the ECJ to undo an EU reform of the carbon market that adds to costs of burning fossil fuel.
Under the PiS government, Poland has become the first in the EU to be put under European Commission watch to ensure it sticks to the rule of law and democratic principles.
Warsaw's intervention on climate, critics say, has only stoked these tensions. "What they're doing nationally, eliminating a proper democratic process, is totally unacceptable in Europe," said Gerben-Jan Gerbrandy, a Dutch lawmaker who is steering the draft climate law through the EU parliament.
EU diplomats say they are growing weary of Polish truculence not just on climate but other policies key to EU cohesion, like migrant quotas that Brussels wants every member state to accept.
"I'm not going to cry for them; they've gotten a lot of sweeteners already," one EU diplomat said.
At Poland's behest, European leaders were left unpicking the minutiae of energy policy at a December summit meant to tackle EU divisions over migration, Britain's vote to exit the EU, and how to handle an increasingly assertive Russia to the east.
"For many months now, Poland only ever appears on our agenda over their domestic problems," another EU diplomat said.
But under the shadow cast on multilateral cooperation by Trump and Brexit, some worry other EU member states will rally around Poland's proposals to dilute climate law.
"It's going to be crucial that the secession of Britain doesn't allow the less progressive voices on climate within the EU to gain traction," said Gregory Barker, climate change minister under former British prime minister David Cameron. (Additional reporting by Gabriela Baczynska; editing by Mark Heinrich)
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