The Department of Justice (DOJ) is trying to put an end to a California program that caps carbon emissions from the transportation sector, arguing the state exceeded its authority by crafting the program alongside Canada.

The program, underway since 2013, aims to improve California’s air quality, allowing companies to trade credits with others in the province of Quebec.

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"The state of California has veered outside of its proper constitutional lane to enter into an international emissions agreement. The power to enter into such agreements is reserved to the federal government, which must be able to speak with one voice in the area of U.S. foreign policy,” DOJ said in a release. “California’s unlawful cap-and-trade agreement with Quebec undermines the president’s ability to negotiate competitive agreements with other nations, as the President sees fit.”

California said it would continue to operate the cap and trade program while fighting the suit.

"This latest attack by the Trump administration is yet another baseless attempt to undermine California's efforts to protect public health and fight climate change. The cap and trade program is an integral part of California's action on climate and we will vigorously defend it in court. Nothing in this complaint changes the current operation of the cap and trade program: we will continue to implement it, including scheduled auctions and compliance requirements," California Air Resources Board Chairwoman Mary Nichols said in a statement.

The government of Quebec likewise said they hoped California would remain in the program.

“The Government of Quebec is committed to the fight against climate change, just like the State of California. We believe that the carbon market is an efficient way to put a price on carbon and that this system is preferable to a direct tax," said Guillaume Simard-Leduc, a spokesperson for the premier of Quebec.

"We obviously wish for them to remain a partner in the carbon-emissions cap-and-trade program and we are in contact with the state government on this matter.”

Environmental groups were quick to defend the legality of the state’s emissions program.

"The administration is yet again not only tearing down critical health protections and safeguards, but is going after others who seek to uphold or extend them,” the Environmental Defense Fund wrote in a statement.

The suit is just the latest move in an ongoing battle between the Trump administration and California.

Recently President Trump Donald John TrumpFederal prosecutor speaks out, says Barr 'has brought shame' on Justice Dept. Former Pence aide: White House staffers discussed Trump refusing to leave office Progressive group buys domain name of Trump's No. 1 Supreme Court pick MORE tweeted he would revoke a California waiver that allows the state to set tougher tailpipe emissions standards, which in turn have been adopted by more than a dozen other states.

Other actions from the Environmental Protection Agency (EPA) have aimed to smear California’s environmental record, threatening to withhold California’s highway funds by hitting the state for violating air quality standards, along with a dubious claim the state’s homeless population was affecting water quality.

“California has long been a leader in fighting climate change for the sake of protecting public health, our natural resources, our economy, and indeed our planet. We will continue leaning forward. We have no plans to back down,” California Attorney General Xavier Becerra Xavier BecerraState AGs condemn HUD rule allowing shelters to serve people on basis of biological sex OVERNIGHT ENERGY: Trump casts doubt on climate change science during briefing on wildfires | Biden attacks Trump's climate record amid Western wildfires, lays out his plan | 20 states sue EPA over methane emissions standards rollback 20 states sue EPA over methane emissions standards rollback MORE said in a statement Wednesday.

California has previously argued it needs environmental regulations that go after transportation pollution in order to meet air quality standards.

California’s cap-and-trade program on transportation emissions has served as a model as multiple New England and mid-Atlantic states embark on a similar regional approach for transportation pollution.

Updated at 3:57 p.m.