The PM’s press secretary said that the email inviting staff members to enjoy the sunshine at a “bring your own booze” event during lockdown was not sent on Mr Johnson’s instruction and he was not among the estimated 100 people to whom it was addressed.
But the press secretary was unable to explain how the prime minister knew that he should attend the event, which he told the House of Commons he joined for 25 minutes in order to thank staff for their work.
Mr Johnson’s claim that he believed the gathering to be a work event would be more difficult to sustain if it could be shown that he saw the invitation sent out by his principal private secretary Martin Reynolds.
Mr Reynolds’ comment that “after what has been an incredibly busy period we thought it would be nice to make the most of the lovely weather and have some socially distanced drinks in the No 10 garden” leave little doubt that it was intended as a social event.
Downing Street confirmed that Mr Reynolds remains in his post - one of the most influential in Mr Johnson’s inner circle - and continues to enjoy the PM’s full confidence.
No 10 refused to confirm whether Mr Johnson’s wife Carrie joined him at the event, as eye-witnesses have suggested.
And the press secretary refused to say whether other ministers took part, whether the prime minister gave a speech and whether he brought a bottle.
She said that all these were issues to be determined by the ongoing inquiry by Whitehall mandarin Sue Gray, whose findings Downing Street does not want to pre-empt.
Downing Street also refused to say whether Tory MP Simon Hoare was right to suggest that the event was in fact a party to welcome back the PM after his return from being treated in hospital for Covid and a thankyou to deputy prime minister Dominic Raab for taking the reins in his absence.
Mr Johnson was treated in intensive care in early April 2020 and went to country residence Chequers to recuperate after discharge, returning to No 10 on 27 April.
In a lengthy grilling by journalists following Mr Johnson’s Commons apology, the PM’s press secretary repeatedly dodged questions on the detail of the event by saying: “Matters around guidance, the nature of any gatherings and attendance are a matter for the independent review to determine.”
No 10 was unable to give any date for the publication of Ms Gray’s report, but said that the PM will publish it in full.
The PM’s official spokesperson declined to commit Mr Johnson to accepting any recommendations by the Whitehall mandarin, pointing out that her remit is to establish the facts around a series of reported parties and she will not necessarily make proposals for action.
“ Sue Gray has the prime minister's backing to carry out this important work and establish the facts,” he said. “Without seeking to preempt the findings of the review, she has his full backing and he will accept the fact that she establishes.”
In response to reporter’s questions, the press secretary denied that the prime minister was “a liar”, but said that the issue of whether he lied about this particular occasion was a matter for the Gray report to determine.
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