The country’s most senior civil servant Simon Case will not be resigning and will not be sacked by Boris Johnson over Partygate.
Whitehall sources named Mr Case, who has not received a fine for partygate, as a scapegoat the Prime Minister could use to deflect attention from himself.
The Gray Report is expected to be heavily critical of the UK's most senior civil servant, accusing him of allowing a rife drinking culture to develop on Downing Street.
Following his receipt of her report – which he has pledged to publish in full – Mr Johnson will make a statement to MPs in the Commons.
Later on Wednesday, he will stage a press conference in Downing Street and address the 1922 Committee of backbench Tory MPs who will have to decide whether the findings are sufficiently serious to warrant a push to oust him.
Ms Gray’s report will give the clearest picture so far of events which led to widespread public anger, including the names of some of those who attended gatherings.
Officials impacted by the inquiry, including those to be named, were written to ahead of its publication, allowing them to have a chance to respond before it was finalised.
Ahead of its release, a Cabinet ally of the Prime Minister said Mr Johnson accepted that there had been “failings” in Government and had apologised for what went wrong.
MP George Eustice told GB News: "All of us including the Prime Minister would prefer that these episodes didn't occur, they shouldn't have happened.
"Sue Gray said in her interim report there'd been a blurring of the lines between things like a drink at the end of the day in a working environment or a send off for somebody who was departing.
"Some of those descended into what it's now clear were actually parties.
"Obviously we'd all prefer that none of this ever happened, myself included, full observed the rules and stayed in lockdown like everyone else.
"We all find it deeply frustrating that these episodes happened right in No.10."
Boris Johnson and Simon Case
Oli Scarff
George Eustice
GB News