California picked up an important partner in its long-running dispute with the Trump administration over vehicle emissions and fuel economy by announcing a deal with Canada to work on pollution reductions.

The agreement comes as the state is in a standoff with its own federal government on the same issues, with little hope of resolving the dispute outside of court.

Few details were offered under the deal announced Wednesday, but it’s clear that Canada would be amenable to stricter regulations that now match those in California and 13 other states, setting up a conflict with the Trump administration’s plans to relax the standards. Canada is in the midst of reviewing its requirements.

Two agencies in the Trump administration are reviewing Obama-era standards and have proposed freezing fuel economy and emissions requirements at 2021 levels. California and the other states likely would reject such a move and go with stronger standards. The administration has threatened to challenge California’s legal right to set its own requirements, granted in 1970 as a way to combat oppressive smog.

Although members of both parties in Congress and the auto industry have urged negotiations to get one requirement nationwide, no talks are scheduled.

“It’s not looking very good at the moment,” Mary Nichols, chairwoman of California’s Air Resources Board, said on a conference call Wednesday.

Two Trump administration agencies, the Environmental Protection Agency and the National Highway Traffic Safety Administration, seem to have rejected the idea of negotiating, Nichols said. “We remain hopeful as long as there’s any opportunity to avert what will otherwise be years of litigation and some degree of confusion,” Nichols said.

Messages were left Wednesday seeking comment from the EPA and the traffic safety agency, both of which have powers to set fuel economy and pollution regulations.

Canadian Environment Minister Catherine McKenna stopped short of saying the country would join California with stricter standards, but said the country is “very interested in options that deliver cleaner cars by making cuts to carbon pollution.” Fuel economy and pollution standards often vary between countries, but the U.S. and Canada have matched in recent years.

At issue is a Trump administration plan to roll back the Obama EPA requirements, which would require cars to get 36 miles (58 kilometers) of real-world driving per gallon (3.8 liters) of gas by 2025. The goal is for Americans to fill up their gas tanks less frequently, sending fewer climate-changing emissions and pollutants into the air, one of the most aggressive measures in place to deal with the impact of climate change.

Instead, the administration has proposed halting the tougher standards at a 2020 requirement that cars achieve 30 miles (48 kilometers) per gallon of real-word driving. Under the Obama rules, California and the federal government were on the same page.

It’s the second effort by the Trump administration to annul initiatives adopted under Obama to rein in fossil fuel emissions. The administration on Wednesday eased restrictions on coal-fired power plants.

Under the deal between California and Canada, the governments will work together on regulations to cut greenhouse gas emissions from light-duty vehicles and to accelerate use of zero-emission vehicles such as electric cars. They’ll also share information on low-carbon fuel requirements, which Canada is developing.

Other states may sign on to California’s stricter standards, Gov. Gavin Newsom said without giving details.

Nichols said California and Canada weren’t sending a message to the Trump administration with the agreement, which came just a week after a congressional committee held a hearing on the matter. She said the agreement has been in the works for a long time.

© The Associated Press. All rights reserved.