WASHINGTON -  More than 190 Democratic lawmakers sued President Donald Trump in federal court on Wednesday, saying he had accepted funds from foreign governments through his businesses without congressional consent in violation of the US Constitution.

The complaint said Trump had not sought congressional approval for any of the payments his hundreds of businesses had received from foreign governments since he took office in January, even though the Constitution requires him to do so. The White House did not immediately respond to requests for comment but has said Trump's business interests do not violate the Constitution. The Trump Organization has said it will donate profits from customers representing foreign governments to the US Treasury but will not require such customers to identify themselves.

At least 30 US senators and 166 representatives are plaintiffs in Wednesday's lawsuit, representing the largest number of legislators ever to sue a US president, according to two lawmakers who are among the plaintiffs.

The Constitution's "foreign emoluments" clause bars US officeholders from accepting payments and various other gifts from foreign governments without congressional approval.

"The president’s failure to tell us about these emoluments, to disclose the payments and benefits that he is receiving, mean that we cannot do our job. We cannot consent to what we don’t know," said Senator Richard Blumenthal, one of the lawmakers bringing the lawsuit, in a conference call on Tuesday.

Representative John Conyers, another plaintiff, added: “President Trump has conflicts of interest in at least 25 countries, and it appears he’s using his presidency to maximize his profits." The Justice Department declined to comment.

Similar lawsuits have been filed in recent months by parties including a nonprofit ethics group, a restaurant trade group, and the attorneys general of Maryland and the District of Columbia.

They allege that Trump's acceptance of payments from foreign and US governments through his hospitality empire puts other hotel and restaurant owners at an unfair disadvantage and provides governments an incentive to give Trump-owned businesses special treatment.

In a motion to dismiss one such lawsuit on Friday, the Justice Department argued that the plaintiffs had not shown any specific harm to their businesses, and that Trump was only banned from receiving foreign government gifts if they arose from his service as president.

On Monday, White House press secretary Sean Spicer said "partisan politics" was behind the lawsuit by the Maryland and District of Columbia officials.

Lawmakers rarely sue the president, so there are few federal court decisions the legislators can cite to prove their legal standing to bring Wednesday's case, said Leah Litman, an assistant professor specializing in constitutional law at the University of California, Irvine.

"But the constitutional provision they're suing to enforce gives them a role in how it's carried out, and that gives them a powerful standing argument," Litman said.

The lawmakers in Wednesday's lawsuit will be represented in court by the Constitutional Accountability Center, a public interest law firm in Washington. Each lawmaker is paying a share of the legal fees from personal or campaign accounts.

Meanwhile, Attorney General Jeff Sessions has denounced as a "detestable lie" the idea he colluded with Russians meddling in the 2016 election, and he clashed with Democratic lawmakers over his refusal to detail his conversations with President Donald Trump.

Sessions, a senior member of Trump's Cabinet and an adviser to his election campaign last year, had a series of tense exchanges with Democrats on the Senate Intelligence Committee during about 2-1/2 hours of testimony as they pressed him to recount discussions with the Republican president.

"You raised your right hand here today and said you would solemnly swear to tell the truth, the whole truth and nothing but the truth," Democratic Senator Martin Heinrich said. "Now you're not answering questions. You're impeding this investigation."

Sessions refused to say whether he and Trump discussed FBI Director James Comey's handling of an investigation into possible collusion between Trump's campaign and Russia during the election campaign before the president fired Comey on May 9.

He also declined to say if Trump opposed Sessions' decision to recuse himself from the Russia probe in March, and whether Justice Department officials discussed possible presidential pardons of individuals being looked at in the probe.

Democratic Senator Ron Wyden told Sessions: "I believe the American people have had it with stonewalling. Americans don't want to hear that answers to relevant questions are privileged."

"I am not stonewalling," Sessions replied, saying he was simply following Justice Department policy not to discuss confidential communications with the president. Sessions' testimony did not provide any damaging new information on Trump campaign ties with Russia or on Comey's dismissal, but his refusal to discuss conversations with Trump raised fresh questions about whether the White House has something to hide.

Adam Schiff, the top Democrat on the House of Representatives' Intelligence Committee, which is conducting a parallel Russia probe, said on Twitter that Congress "must compel responses using whatever process necessary."

READ MORE: Power of speech

Last week, Comey told the Senate committee that Trump had fired him to undermine the FBI's investigation of the Russia matter.

Trump's decision to fire Comey, a move recommended by Sessions despite having already recused himself from the Russia probe, prompted critics to charge that the president was trying to interfere with a criminal investigation.

Senator Angus King, an independent, questioned Sessions' legal basis for refusing to answer questions after Sessions said Trump had not invoked executive privilege regarding the conversations.

Executive privilege can be claimed by a president or senior government officials to withhold information from Congress or the courts to protect the executive branch decision-making process.

Sessions said it would be "inappropriate" for him to reveal private conversations with Trump when the president "has not had a full opportunity to review the questions and to make a decision on whether or not to approve such an answer."

Legal experts said there was some merit to Sessions' argument.

Andrew Wright, a professor at Savannah Law School and associate counsel under former President Barack Obama, said it was not unusual for government employees to refuse to discuss conversations with the president in order to preserve the right to invoke executive privilege later.

Sessions' clash with the Democratic senators was the latest chapter in a saga that has dogged Trump in his first five months as president and distracted from his domestic policy agenda including major healthcare and tax cut initiatives.

"The suggestion that I participated in any collusion or that I was aware of any collusion with the Russian government to hurt this country, which I have served with honor for over 35 years, or to undermine the integrity of our democratic process, is an appalling and detestable lie," Sessions said.

"I have never met with or had any conversation with any Russians or any foreign officials concerning any type of interference with any campaign or election in the United States. Further, I have no knowledge of any such conversations by anyone connected with the Trump campaign."

US intelligence agencies concluded in a report released in January that Russian President Vladimir Putin ordered an effort to interfere in the election to help Trump in part by hacking and releasing damaging emails about Democratic candidate Hillary Clinton.

Russia has denied any such interference, and Trump has denied any collusion by his campaign with Moscow.

Sessions recused himself from the Russia investigation in March after revelations that he had failed to disclose two meetings last year with Russia's ambassador to Washington, Sergei Kislyak.

In his testimony on Tuesday, Sessions addressed media reports that he may have had a third previously undisclosed meeting with Kislyak at Washington's Mayflower Hotel last year.

Sessions said he did not have any private meetings and could not recall any conversations with any Russian officials at the hotel but did not rule out that a "brief interaction" with Kislyak may have occurred there.

A former Republican senator, Sessions was an early supporter of Trump's presidential campaign, but sources say there has been tension between the two men in recent weeks because Trump was annoyed that Sessions recused himself from the Russia probe.

Sessions said on Tuesday he did not recuse himself because he felt he was a subject of the investigation himself but rather because he felt he was required to by Justice Department rules.