A coalition of 16 US states led by California has sued Donald Trump’s administration over his decision to declare a national emergency in order to fund a wall along the Mexico border.

The lawsuit was filed on Monday in the US district court for the northern district of California after Trump invoked emergency powers on Friday when Congress declined his request for $5.7bn to help create his signature policy promise.

His move aims to let him spend money appropriated by Congress for other purposes.

The states’ lawsuit represents part of an unfolding wave of anticipated legal challenges to Trump’s novel scheme for building a border wall, which polling shows a majority of voters do not want and which his own party declined to fund for two years when Republicans controlled both houses of Congress.

Democratic House speaker Nancy Pelosi, who was swept back to power in the midterm elections late last year, vowed that Congress would join the legal effort to block Trump’s emergency declaration.

“The president’s actions clearly violate the Congress’s exclusive power of the purse, which our founders enshrined in the constitution,” said Pelosi in a joint statement with Senate majority leader Chuck Schumer. “The Congress will defend our constitutional authorities in the Congress, in the courts and in the public, using every remedy available.”

Legal scholars disagree about whether Trump’s emergency declaration falls within constitutional bounds. In a rambling riff on the question delivered as an aside to his declaration of emergency on Friday, Trump predicted the matter would be appealed to the US supreme court.

“And we will have a national emergency, and we will then be sued, and they will sue us in the ninth circuit, even though it shouldn’t be there, and we will possibly get a bad ruling,” said Trump, “and then we’ll get another bad ruling, and then we’ll end up in the supreme court, and hopefully we’ll get a fair shake and we’ll win in the supreme court.”

California attorney general Xavier Becerra is leading the states’ lawsuit against the administration. He said: “Today, on Presidents’ Day, we take President Trump to court to block his misuse of presidential power.”

Becerra, a Democrat, added: “We’re suing President Trump to stop him from unilaterally robbing taxpayer funds lawfully set aside by Congress for the people of our states. For most of us, the Office of the Presidency is not a place for theatre.”

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Trump criticized California’s lead role in the multi-state lawsuit challenging his emergency declaration to pay for the wall. On Twitter on Tuesday, Trump noted last week’s decision by California Governor Gavin Newsom to cancel a high-speed rail line between Los Angeles and San Francisco. Trump claimed, without citing evidence, that the “failed Fast Train project” had become “hundreds of times more expensive than the desperately needed Wall!”

Three Texas landowners and an environmental group filed the first lawsuit against Trump’s move on Friday, saying it violated the constitution and would infringe on their property rights.

The legal challenges could slow Trump’s efforts to build the wall, which he says is needed to check illegal immigration and drug trafficking, and the case is likely to end up in the conservative-leaning US supreme court.

Facebook Twitter Pinterest Activists rally against Trump’s declaration of a national emergency. Photograph: UPI/Barcroft Images

In a budget deal passed by Congress to avert a second government shutdown, nearly $1.4bn was allocated to border fencing. Trump’s emergency order would give him $6.7bn beyond what lawmakers authorised. The move allows the president to bypass Congress to use money from the Pentagon and other budgets.

In television interviews on Sunday and Monday, Becerra said the lawsuit would use Trump’s own words against him as evidence there was no national emergency to declare. Earlier, Trump had said he knew that he did not need to declare an emergency to build the wall, a comment that could now undercut the government’s legal argument.

“Presidents don’t go in and claim declarations of emergency for the purposes of raiding accounts because they weren’t able to get Congress to fund items,” Becerra said on MSNBC.

California has repeatedly challenged Trump in court. Becerra has filed at least 45 lawsuits against the administration.