Aides of Boris Johnson were "touching each other up" during a "debauched" party at Downing Street during lockdown, it has been claimed.
Witnesses have spoken of couples becoming intimate with each other at one party, that took place the night before the Duke of Edinburgh's funeral.
ITV News journalist Paul Brand told Times Radio on Thursday morning that the party, which was not attended by Johnson, "contained more debauchery than you can ever imagine".
The claims come in a new ITV podcast called Partygate: The Inside Story.
Brand said: "We are told that couples were kissing at the party – and obviously this was a time of social distancing – and these were allegedly fresh couplings... people who should have been socially distancing.
"This was a time when the Queen was unable to be with her family, mourning her own life partner... and yet here were fresh couplings in Number 10, flouting those rules and getting together."
The podcast also suggests at least two couples were “getting it on with each other” and “touching each other up” and two other members of staff were “all over each other” in a kitchen area.
The gathering, which took place on 16 April, 2021, was held at a time when people in England were still under strict lockdown rules.
The following day, the Queen was pictured sitting alone at the funeral of her husband while adhering to the social distancing rules in place.
Watch: Whistleblower says Boris Johnson joked about lockdown party
Lockdown-busting parties held at Downing Street led to Johnson losing support from his party amid a scandal-ridden period that ultimately led to his resignation in July 2022.
The fresh claims may hurt his hopes of making a political comeback, which he is reportedly planning if the Tories continue to flounder in the polls under Rishi Sunak.
They will also put Johnson under further pressure as he faces a parliamentary investigation into whether he misled MPs over the so-called Partygate scandal.
ITV News has also reported on Johnson allegedly joking at a boozy Number 10 leaving do during the coronavirus pandemic that staff were at “the most unsocially distanced party in the UK”.
A spokesman for Johnson did not deny the comment but insisted the then-PM had “worked constantly” to ensure the government did all it could to save lives and protect livelihoods during the pandemic.
ITV News reported that the comments were made as staff gathered around a table filled with alcohol and party snacks to hear him toast his outgoing director of communications, Lee Cain, in November 2020.
At the time of the event, England was covered by a second national lockdown with indoor gatherings banned except for in certain circumstances such as for “work purposes”, and social distancing remained the rule in workplaces.
It reports that a source said: “I was working late – some music came on, the mumbling sort of rose, and there were loads of people stood around, but this time I came out because I heard the prime minister speaking and that’s when I heard the quote: ‘This is the most unsocially distanced party in the UK right now’ and everyone was laughing about it.”
Johnson was fined as part of a police investigation into gatherings held in Downing Street while social distancing restrictions were in place.
However, he was fined for attending his own birthday party in the Cabinet Room in Downing Street in June 2020 rather than for the alleged party the ITV source mentions.
He is still due to appear before the Commons privileges committee over comments he made to MPs from the despatch box about Partygate, insisting that he believed rules were followed in No 10.
Deputy Labour leader Angela Rayner said: “As the disgraced former prime minister plots his comeback, he reminds us all yet again why he’s totally unfit for office.
“While people were unable to say goodbye to loved ones or mourn with their families, he was breaking his own rules with reckless abandon and then lying to the British people."