Warsaw, Apr 18 (IANS): The European Court of Justice (ECJ) has ruled that increased logging in Poland's ancient Bialowieza forest has violated EU environmental laws and the country was facing massive fines.

At least 10,000 trees have been felled in the ancient forest, which is a Unesco World Heritage Site nourishing plenty of animals and plants, including Europe's largest herd of bison, Xinhua news agency reported.

A minimum fine of 4.3 million euros (about $5.3 million) could be levied against Poland unless the tree felling is stopped, the court ruled on Tuesday.

"If they comply with the judgment, no problem. If they don't, we have a possibility to go to a second infringement procedure that may end up in fines," a European Union official said on Tuesday.

Unesco has classified the forest nestled across Poland and Belarus on the watershed of the Baltic and Black Seas as a site of "outstanding universal value".

Poland argued that its decision to increase logging was necessary to combat a beetle infestation.

But the ECJ found that Poland's own documents showed logging posed a greater threat to Bialowieza's integrity.

The ECJ ruling was hailed by environmental activists.