Sue Gray is putting the final touches to her report on anti-lockdown parties in Downing Street, after a deadline for people she plans to name to raise objections expired.

A source in Whitehall suggested that some of the senior officials told by Gray that they would be identified would have opposed it; but she had taken the time to address their concerns and move forward with the release of her final findings this week.

Tory MPs are awaiting full details of what happened in Downing Street and Whitehall during a series of rallies for which 126 fines have now been issued – including only one to the Prime Minister.

A former minister said the fact Johnson had only been fined once eased the immediate pressure on him, but added: ‘I wouldn’t have thought the Prime Minister was out of the woods before summer vacation. There are many things that could still go wrong.

As Sunday’s deadline approached, Education Secretary Nadhim Zahawi struggled to answer the question of why Gray recently met Boris Johnson face-to-face, repeatedly insisting that he did not know who called the meeting or what was discussed.

Downing Street maintains that Gray did it. “Sue asked for the reunion, it’s 100% true,” a Number 10 source said – although she admitted she couldn’t rule out she may have done so in response to the someone’s initial prompt in issue 10.

Gray’s allies suggested the request came from Johnson’s team. Labor’s Angela Rayner called on the government to “urgently explain” what was being discussed.

Asked by Sophy Ridge on Sky News, Zahawi said: ‘I don’t know the details of all the meetings taking place at No 10. What I do know is that the Prime Minister never intervened in the meeting. investigation led by Sue Gray. He always wanted her to go where the evidence leads her,” he said.

“I worked with Sue Gray, I knew Sue Gray. I know she has the highest level of professionalism and her integrity is unquestionable. She did not pull out of the game in her first report.

Pressed for more details about the meeting between Gray and Johnson, Zahawi said: “Meetings are happening every day, my diary is full of meetings. You can ask me a question: ‘Who put this meeting on my calendar?’ …it will be in my journal because someone on my team thought it was the right thing to do.

Gray’s report is expected to be released this week, and up to 30 officials have been told they could be directly named or easily identifiable. They had until 5 p.m. Sunday to respond.

They are expected to include Cabinet Secretary Simon Case, the most senior civil servant, who is seen as a likely scapegoat despite not being fined.

Case is accused by some junior officials of failing to take responsibility for the drinking culture that developed in No. 10, or of shielding them from an investigation that led to junior officials receiving several fines, while he escaped without blame.

Gray was appointed to take over the Case party investigation in December, after it was revealed that he hosted an event at his office for which invitations were sent out saying “Christmas party!”. A government spokesman said at the time that officials from Case’s office had taken part in a “virtual quiz”.

The case was due to appear before MPs in the Public Administration and Constitutional Affairs Committee on Tuesday, but ministers unexpectedly canceled the hearing last week shortly after it was announced.

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The Metropolitan Police revealed on Thursday that they have completed their investigation into anti-lockdown rallies in Downing Street and Whitehall.

The Prime Minister was given a fixed fine notice for the birthday party held in the Cabinet Room in June 2020. The Chancellor, Rishi Sunak, and Johnson’s wife, Carrie Johnson, were also fined for attending the same event.

Many Tory officials and MPs have expressed surprise that the Prime Minister has not received further fines, especially as he is known to have attended some of the events for which others have reportedly been fined.

Johnson is expected to make a statement to parliament when Gray’s report is released. He will then face an investigation by the House of Commons Privileges Committee into whether he misled MPs when the Partygate stories first emerged by insisting that “all guidelines were followed” in issue 10.