BRUSSELS (Reuters) - Tesla (TSLA) has joined BMW and Chinese producers in filing a challenge at the Court of Justice of the European Union (CJEU) against EU tariffs on China-made electric vehicles, according to a filing on the court's website on Monday.

The challenge will open a new front in Brussels' conflict with Elon Musk, Tesla CEO and ally of U.S. President Donald Trump. Earlier this month, the EU stepped up its probe into Musk's social media platform X over content moderation.

The EU imposed tariffs on China-made EVs at the end of October after an anti-subsidy investigation. The rate for Tesla was 7.8%, lower than any of its competitors.

The court document showed the U.S. automaker lodged its complaint at the General Court, the lower of two CJEU chambers, last Wednesday, the deadline for filing challenges. Proceedings at the General Court last on average 18 months and can be appealed.

No further details of the cases were given.

BMW, Chinese electric vehicle makers BYD (BYD), Geely (GELYF) and SAIC, and auto sector body CCCME have also challenged the EU's import tariffs at the court.

(Reporting by Philip Blenkinsop; Editing by Mark Potter)