Two Downing Street aides have denied telling Boris Johnson that all Covid guidance was followed.

Both Simon Case, who was the Cabinet Secretary, and Jack Doyle, who was director of communications at the time when partygate emerged, replied "no" when asked if they had assured Mr Johnson that the guidance was adhered to at all times.

The privileges committee has published its 110-page partygate evidence dossier this morning, just hours before Boris Johnson will face a grilling which could determine his future as an MP.

Here are the key points we have gleaned from the document:

Simon Case: I never assured PM Covid rules were followed

Mr Case told the privileges committee he never reassured Mr Johnson Covid rules were followed in No 10.

Asked whether he gave the PM “any assurances” that rules and guidance were adhered to at all times, and that no parties were held in No 10 when Covid restrictions were in force, Whitehall’s top civil servant replied “no”.

He also said he did not know of anyone else who gave Mr Johnson any such assurance.

It comes despite an MP suggesting Mr Case likely told Downing Street that no Covid rules were broken.

Sarah Dines, who was Mr Johnson’s private secretary, told the committee about a conversation in the Cabinet Room where the then-prime minister asked: “We did follow the rules at all times, didn’t we?”

She went on to say: “I recall more than one person in the room said ‘Yes, of course.’ I am not certain who the people who said yes, but I am certain they were civil servants and it was more than one voice. I am about 90 per cent sure one of them was Simon Case, the Cabinet Secretary.”

Jack Doyle: I never told PM guidance was adhered to 'at all times'

In his own evidence to the committee, Mr Doyle denied giving Mr Johnson any assurances that Covid guidance was "adhered to at all times" in Downing Street during lockdown.

"We made every effort to comply with the Covid-19 guidelines to the greatest extent that we were able," he added.

"It is difficult to say that the guidelines of this nature [e.g. Perspex screens] were followed at all times, and it would not be possible for me to say that they were."

Lee Cain: Garden party was ‘purely a social function’

Lee Cain, who was Mr Johnson’s director of communications for the first part of the pandemic, said it was “clear” that the garden party in May 2020 was “purely a social function”.

Mr Johnson has said that he understood the gathering to be a “socially-distanced outdoor meeting to boost staff morale and teamworking after what had been a very difficult period”.

He added: “In my view, an opportunity to thank staff and boost morale was essential for work purposes.”

But in evidence cited by the committee, Mr Cain said: “From memory there were around 40 people in attendance including the PM, the PPS, Mrs Johnson and - unusually - advisers from other departments.

“It was clear observing all who attended and the layout of the event that this was purely a social function."

They were joined by a cross-section of staff from across Downing Street.

Dominic Cummings: ‘Comical’ for Johnson to suggest he thought garden party was ‘work’

Dominic Cummings also took aim at Mr Johnson over his interpretation of the "BYOB" event organised by Martin Reynolds, who was the PM's principal private secretary.

Mr Johnson's former top aide said the garden party was a “mistake”, and insisted he had not given his old boss any reassurances around it.

Mr Cummings is also quoted as having told the Cabinet Office investigation team: "The idea the PM could have thought this drinks event was 'work' is comical, given the tables covered in bottles of drink, everyone standing around drinking etc.

"The PM certainly knew it was a drinks party because I told him and when he walked outside he saw a drinks party."

Jack Doyle: ‘Just be robust and they’ll get bored’

Privileges Committee evidence reveals Mr Doyle told a No 10 official "just be robust and they'll get bored" when first approached by a journalist over partygate.

Mr Doyle told the aide to "say something as robust as we can manage" when Pippa Crerar, the then political editor of the Daily Mirror, approached No 10 over drinks that took place in December 2020 at Downing Street.

"Key thing is there were never any rules against workplace drinking, so we can say with confidence no rules were broken. Ignore the Xmas quiz' bulls--t – who cares. Just be robust and they'll get bored,” Mr Doyle wrote.

Martin Reynolds: I questioned if Johnson’s PMQ line was ‘realistic’

Mr Reynolds questioned Mr Johnson's plan to tell the Commons that all rules had been followed.

The former aide said he questioned how "realistic" Mr Johnson's comments were.

"He did not welcome the interruption but told me that he had received reassurances that the comms event was within the rules,” he said.

"I accepted this but questioned whether it was realistic to argue that all guidance had been followed at all times, given the nature of the working environment in No 10."

Lee Cain: PM was warned about 'BYOB' event

Mr Cain said Mr Cummings agreed with him that the May garden party should not take place and later raised the issue with Mr Johnson.

But when they spoke, the pair were said to have argued about "multiple staffing issues".

Mr Cain said he did not recall “personally” having a conversation with Mr Johnson about the gathering, but it would have been “highly unusual” for him not to have raised a “potentially serious communications risk” with the PM.

Mr Johnson said in his evidence to the parliamentary inquiry: “I can categorically state that no one at the time expressed to me any concerns about whether the event complied with the Rules or Guidance.

"I do recall a conversation with Dominic Cummings on the afternoon of the event, but he did not mention the event, let alone express any concerns that the event would breach the Rules or Guidance."