Washington sued the U.S. Postal Service on Wednesday, trying to block the Trump administration’s proposed rules that could throw the state’s vote-by-mail system into chaos just two months before this year’s midterm elections.

It’s the second time the state has sued to block this executive order. The Supreme Court on Monday sided with the Trump administration, finding that Washington and other states’ prior lawsuits were filed prematurely. The court did not rule on the substance of the executive order or the lawsuits, only the timing.

“This rule was written to satisfy the president’s continued desire to control our vote, but the U.S. Constitution is clear: States control elections,” Washington Attorney General Nick Brown said at a news conference in Seattle. “The president and the Postal Service have no role. This rule is not a serious policy. It is illegal, it is costly and it is frankly impossible to implement.”

Trump seeks to remake how states that use vote by mail conduct elections. His order requires states to hand over private voting lists to the federal government, which would then maintain a national list of eligible voters. The rule tells the Postal Service to deliver ballots only to voters on that list. The postmaster general has further said that the Postal Service would not deliver ballots in states that do not hand over their voter lists.

The rule would require bar codes on ballot envelopes (Washington currently has bar codes on the envelopes that are sent to voters but not on the return envelopes) and would require the Postal Service to approve envelope design.

“It’s clear that the federal government is trying to take over our elections,” said Washington Secretary of State Steve Hobbs, who appeared with Brown on Wednesday. “We are prepared to fight every step of the way to stop that from happening.”

Hobbs said the state’s 5.1 million ballots are already printed and will begin to be mailed to overseas voters in just three weeks. Hobbs said he was confident the lawsuit would succeed in blocking the new regulations, but that if it failed, voters should use drop boxes to return their ballots to reduce the risk of the Postal Service not delivering them.

The lawsuit, filed by 25 states in federal court in Massachusetts, argues that now that the Postal Service has published a new rule to comply with Trump’s order, the court can judge the issue on its merits.

“Congress has not afforded USPS any authority whatsoever to set rules for federal elections or mail voting, even though Americans have cast ballots by mail for generations,” the lawsuit says.

It argues that the administration’s rules are both illegal and logistically impossible.

“The president’s challenges to our elections strike at something fundamental to our democracy,” Brown said.

This year’s executive order comes after a similar order made last year by the president was blocked in court. Trump has unsuccessfully pressured Congress to pass a plan to restrict mail ballots.

The lawsuit points, in its opening paragraphs, to Trump’s own words to argue that the administration’s efforts are a partisan attempt to gain advantage, not a sincere concern over election security.

“One need not look further than the White House to explain USPS’s unprecedented and unlawful conduct,” the lawsuit says. “President Trump has long opposed mail voting, expressing that it would ‘LEAD TO THE END OF OUR GREAT REPUBLICAN PARTY.'”