The EU risked reopening a bitter feud with China over solar panel manufacturing after confirming Thursday it had launched a fresh trade probe into a key part of the sector.

Confirming media reports, European Commission spokesman Daniel Rosario said EU trade authorities opened an investigation last month into alleged price dumping by China on solar glass, a key component of solar panels.

A 2013 trade row over solar panels sparked the EU's biggest-ever trade probe covering a market worth some 21 billion euros ($25 billion) at its zenith.

But last July, Brussels and China came to a hard-won agreement, ending heated rounds of tit-for-tat measures that included a Chinese probe into European wine imports.

Estimated at about 210 million euros, solar glass manufacturing is just a small component of the panel market in Europe.

Launched on December 19, the EU has nine months to gather information on the solar glass case and decide whether to move forward with an official complaint.

Rosario insisted the probe was unrelated and much narrower than the now resolved feud over solar panels.

"This is a stand-alone investigation concerning a clearly distinct product and analysing imports during a different period," Rosario told AFP.

But EU manufacturers argue illegally low pricing by China of solar glass is killing European jobs.

"The prices are absurdly low," said Ulrich Frei, president of the EU ProSun lobby group that spearheaded the original campaign against the Chinese solar panel industry.

"The prices are under the manufacturing costs, even when (import) duties are included," he added.

EU ProSun has been a fierce critic of Chinese manufacturers which it says have put Europe's solar panel industry in the shade by dumping their products below cost on the European market.