"The state of California has veered outside of its proper constitutional lane to enter into an international emissions agreement," Assistant US Attorney General Jeffrey Clark said in the release. "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 US foreign policy".
The US Constitution forbids individual states from making treaties or similar agreements with foreign countries.
The lawsuit filed on Wednesday in the Eastern District of California charges California with conducting an independent foreign policy on greenhouse gases by entering a cap-and-trade program with Quebec in 2013, according to the release.
Quebec Premier François Legault said earlier in the day he would prefer the US state to remain in the agreement but noted that he is still prepared to go it alone if necessary.