Sue Gray’s inquiry into No 10 parties will carry on, despite the police announcing its own probe into the scandal – but its report is expected to be delayed.
The Cabinet Office made clear the investigation – which is likely to determine whether Boris Johnson survives in power – is ongoing, despite suggestions it would be “paused”.
However, it may not emerge for several weeks, while the police carry out their own inquiries, having been expected to be released at the end of this week, prolonging the agony for the Tory party.
“The investigation being carried out by Sue Gray is continuing. There is in ongoing contact with the Metropolitan Police Service,” the Cabinet Office said.
The statement came after Mr Johnson suffered the enormous blow of the Metropolitan Police announcing an investigation – after months of refusing to get involved.
Most significantly, it has acted after receiving evidence from Ms Gray herself that she believes breaches of Covid rules may have taken place during lockdowns – despite the prime minister’s denials.
The senior civil servant’s terms of reference stated that her inquiry “may” be paused if the police stepped in and Downing Street had briefed that it would be.
The Gray and Met verdicts will determine whether 54 Conservative MPs submit letters demanding a no-confidence vote in the prime minister, the number required to trigger it.
The Met had faced fierce criticism for sitting on the sidelines, arguing it did not investigate alleged breaches of coronavirus rules retrospectively.
But, at a meeting of London Assembly’s Police and Crime Committee, the commissioner Cressida Dick said “We have a long-established and effective working relationship with the Cabinet Office, who have an investigative capability.
“As you well know they have been carrying out an investigation over the last few weeks.
“What I can tell you this morning is that, as a result of the information provided by the Cabinet Office inquiry team and, secondly, my officers’ own assessment, I can confirm that the Met is now investigating a number of events that took place at Downing Street and Whitehall in the last two years in relation to potential breaches of Covid-19 regulations.”
Labour announced it had secured an urgent question, to drag a government minister to the Commons despatch box about the latest dramatic development.
“With Boris Johnson’s Downing Street now under police investigation, how on earth can he think he can stay on as prime minister?” asked Angela Rayner, the party’s deputy leader.
Sadiq Khan, the Mayor of London, welcomed the investigation, saying:: “I have been clear that members of the public must be able to expect the highest standards from everyone, including the prime minister and those around him.
“No one is above the law. There cannot be one rule for the government and another for everyone else.”
