Journalists have accused Senate officials of banning them from filming or recording audio in hallways, a move that prompted an outcry from Democrats and free-speech advocates.

The apparent move - which would break with decades of tradition – sparked an afternoon of confusion. Journalists from various organisations said that had been told to stop filming unless they had prior permission from Senators, raising fears that access was being restricted amid a number of important events, including the passing of a new healthcare act and testimony in investigations against Russia's alleged meddling in the presidential election last year.

The American Civil Liberties Union was one group to decry the move, with the organisation's political director Faiz Shakir saying: “Closing the shutters now, while Congress is secretly considering a bill that would cause over 20 million people to lose health insurance, is utterly unreasonable and flies in the face of the First Amendment.”

Crowds of reporters in the Capitol’s hallways have recently hit record sizes, as journalists seek to cover the often unprecedented workings of the Trump administration.

Last month, in the wake of scandals that rocked the White House, the directors of the Senate Media Galleries – print and broadcast – sent a letter to bureau chiefs and editors saying that the Capitol “has reached its capacity for reporters.”

“Collectively, the press following Senators have become large and aggressive,” officials with the two galleries wrote. “We are concerned someone may get hurt.”

In a tweet responding to the apparent move, Democratic Senator Amy Klobuchar – ranking member on the Senate Rules Committee, who would be the group to impose such a move – called “on the majority to allow reporting in the Capitol to proceed as usual.”

Democratic Senator Chris Murphy also lambasted the rule change, tweeting, “Maybe not the right moment to lower the secrecy veil on Congress. To whoever is trying to protect Senators – we can fend for ourselves.”

In response, the Senate Rules Committee denied issuing new restrictions, while press gallery staffers refused to explain their part in the drama.

“The Rules Committee has made no changes to the existing rules governing press coverage on the Senate side of the Capitol complex,” the Rules Committee chairman, Senator Richard Shelby (R-Ala.), said in a statement. “The Committee has been working with the various galleries to ensure compliance with existing rules in an effort to help provide a safe environment for Members, the press corps, staff and constituents as they travel from Senate offices to the Capitol.”

Ms Klobuchar later tweeted that she had spoken to Senator Shelby and that he had said “he wouldn't [make a] change to press access without consulting me.” In another tweet, she added: “This is no time for limiting press access in U.S. Senate. Russia hearings, Sessions testifying & (secret?) health care bill being drafted!”

Reporters were then told that they “may continue to follow the rules as if it was yesterday”, according to NBC reporter Kasie Hunt.

Ms Klobuchar said she would fight any possible attempt to change the rules, telling journalists at the Capitol: “You don’t shut down the press if you don’t want to do interviews.”