Uber is suing London's transport regulator in the latest skirmish over rules that may harm the controversial company's business.

Uber will ask London judges to decide the legality of rules that require drivers from non-English speaking countries to pass a language exam, the company said in a statement. The measures also force Uber to notify Transport for London of any changes made to its mobile-phone app.

"This legal action is very much a last resort," Tom Elvidge, Uber London's general manager, said in the statement. "We're particularly disappointed that, after a lengthy consultation process with Transport for London, the goalposts have moved at the last minute and new rules are now being introduced that will be bad for both drivers and tech companies."

San Francisco-based Uber has fought with regulators around the globe over the technology that traditional taxi companies say threatens their existence. In London, Uber won a suit against TfL over the use of its app as a taxi meter and is still waiting for a ruling in an employment dispute with drivers.


TfL, which oversees London's buses, subways and cycle paths as well as private-hire cars, said that the new rules were designed to boost safety.

"We responded to Uber's letter and will be robustly defending the legal proceedings," TfL said in a statement. The rules "have been introduced to enhance public safety when using private hire services and we are determined to create a vibrant taxi and private hire market with space for all providers to flourish."

Uber rivals were quick to back TfL, with Addison Lee Ltd. saying that Uber had reversed its position on the new measures.

"Having previously backed the proposals it's hard to understand Uber's resistance to implementation of these new regulations," Andy Boland, Addison Lee's chief executive officer, said in a statement Wednesday. "The whole industry was fully involved in the consultation."