LONDON — Britain’s embattled art trade, already rattled by the potential fallout from Brexit, is bracing for new rules intended to tackle money laundering and terrorism financing that some fear could further hamstring dealers in the country.

As of Friday, “art market participants” in Britain are subject to the regulations when conducting transactions worth more than 10,000 euros, or about $11,100. Under the rules, they have to register with the government’s tax agency, and dealers and auctioneers must establish the identity of the “ultimate beneficial owner” — meaning both seller and buyer — before entering into a transaction.

The legislation, ratified last month by the British Parliament, introduces largely without modification a European Union directive that is at various stages of implementation in other countries in the bloc.

“This is very serious. It could potentially change commonly accepted market practices,” said Kenneth Mullen, a partner at the London-based law firm Withers. “Due diligence is going to be fundamental. It does seem to mark a shift toward a more regulated industry.”