Senior Conservatives have continued to question the government over the police escorts Taylor Swift received to her concerts at Wembley Stadium in August.
Ministers have denied interfering with the Metropolitan Police's operational independence.
In the Commons, shadow leader of the House Chris Philp urged the government to make a statement and "come clean"; while Tory former minister Harriett Baldwin called for a debate on the government's approach to breaches of the ministerial code.
Commons leader Lucy Powell suggested Tory MPs should move on, taking inspiration from one of the singer's biggest hits when she said: "It's about time they 'Shake It Off'."
Powell also quoted a comment by composer, musical impresario and Conservative peer Lord [Andrew] Lloyd Webber in The Times, that the Tories' "continued attention" on this was "ludicrous".
The exchanges come after a row centred around the prime minister's attendance at one of the star's sell-out shows, and the news that Mayor of London Sadiq Khan and Home Secretary Yvette Cooper were involved in talks about security for the concerts after which Swift was granted a blue-light escort - a type of protection usually reserved for royalty and senior politicians.
A motorbike convoy escorted her to Wembley despite initial reservations about the arrangement from the police.
Philp told MPs the government needed to "come clean and tell the truth".
"It is reported the police decided initially that no special escort was needed. Apparently the home secretary, the attorney general, the mayor of London and, inevitably, [the PM's former chief of staff] Sue Gray then pressured the police into changing their mind and providing one, violating the police's operational independence.
"We now know that one of the many freebies the prime minister has eagerly scrounged for himself were tickets and a backstage pass to that very concert."
He went on to list other Labour ministers who received free tickets, saying: "What were they doing, having a cabinet meeting at the concert?
"Does the leader [Powell] understand how bad this looks? The government initially denied the Met were pressured, which now appears to be untrue."
Responding to a heckle, Powell said: "No, I wasn't there actually."
She also pointed to the Swift shows generating £1bn for the UK economy this summer, adding: "Surely this is something that people want to welcome."
She strongly rejected suggestions the Met's operational independence had been compromised, saying "these issues are totally taken operationally by the police".
Powell added that Swift had been "subject to a very serious threat to her safety only a few days before coming to the UK".
The singer's shows in Vienna were cancelled because of a threat of a terrorist attack.
Southport attack
Sir Keir and his family spoke to Swift and her mother for around 10 minutes at one of her Wembley shows.
It is understood there was no discussion of security arrangements, and that the conversation focused on the Southport stabbings , which took place during a children's Swift-themed dance workshop in July.
Three girls aged between six and nine were killed and 10 other people - eight of them children - were wounded.
Powell said the PM wanted to thank Swift for her support for the families affected by the attack.
Earlier this month Sir Keir repaid the cost of tickets to the show he received from Universal Music.
Earlier, Education Secretary Bridget Phillipson said "many" ministers were "lucky" to receive tickets to Swift shows, but she was "not quite sure" how a conflict of interest would arise over her accepting them.
She told BBC Radio 4's Today programme: "I am aware as a member of the cabinet that it is important I follow everything that's asked of me in terms of declarations both as an MP, through the register of members' interests, but also my responsibilities under the ministerial code."
On Tuesday, Downing Street denied Sir Keir had received free tickets as a "thank you" for the singer getting a police escort.
Conservative former cabinet minister Sir Jacob Rees-Mogg told GB News Sir Keir's behaviour was "beneath his dignity, and it’s certainly beneath the dignity of his office".