WASHINGTON (Reuters) - Legislation to impose new sanctions on Russia and Iran that passed the U.S. Senate nearly unanimously last week has run into a procedural problem that could prevent a quick vote in the House of Representatives, lawmakers said on Tuesday.

FILE PHOTO: Iran's national flags are seen on a square in Tehran February 10, 2012, a day before the anniversary of the Islamic Revolution. REUTERS/Morteza Nikoubazl/File Photo

The Countering Iran’s Destabilizing Activities Act, which also includes new sanctions against Russia, passed the Senate 98-2 last week, an overwhelming vote that looked like it might complicate President Donald Trump’s desire for warmer relations with Moscow.

But the measure must still pass the House before it can be sent to Trump to sign into law, or veto, and the House parliamentarian found that the legislation violated a constitutional requirement that any bill that raises revenue for the government must originate in the House, something known as a “blue slip” violation.

“The final bill, and final language, violated the origination clause in the Constitution,” Representative Kevin Brady, the Republican chairman of the House Ways and Means Committee, told reporters.

Democrats suggested that Republicans were stalling the bill out of loyalty to Trump, whose administration has criticized the sanctions package as potentially too restrictive. In the past, Democrats said, House leaders had overcome such objections without discussion by quickly voting on identical versions of Senate legislation.

“This is nothing but a delay tactic and the public shouldn’t be fooled by complex-sounding parliamentary procedure,” said Representative Eliot Engel, ranking Democrat on the House Foreign Affairs Committee.

Republicans insisted it was a procedural, not a policy, matter, noting that the Russia amendment to the Iran bill was 100 pages long and passed in the Senate only last week.

“I strongly support sanctions against Iran and Russia to hold them accountable,” Brady said.

Brady said House leaders were working with the Senate and House Foreign Affairs Committee to determine how to proceed, but the Senate could address the issue by quickly updating the bill and sending it back to the House.

Trump’s fellow Republicans hold a majority of 52 seats in the 100-member Senate, and a more commanding 238- to 193-seat margin in the House.

Brady could not predict when the House might vote, including whether it would be before Congress’ summer recess starts at the end of July.

Cory Fritz, a spokesman for Ed Royce, the Republican chairman of the House foreign affairs committee, said the committee is reviewing the bill.