It comes amid reports the prime minister has regrouped allies from his victorious 2019 leadership campaign in order to shore up support among Conservative MPs in the face of the looming prospect of a no confidence vote.
While some Tory backbenchers have openly called for Mr Johnson to resign – including the former cabinet minister David Davis – many are reserving judgement until the publication of Ms Gray’s report, which is expected next week.
But in a row over the publication of the document, Angela Rayner, Labour’s deputy leader, stressed that “all accompanying evidence” must be disclosed after Ms Gray, a senior civil servant, presents her report to the prime minister.
It comes after The Guardian reported that some evidence, including emails, text messages and transcripts of interviews, will not be made public. Under the terms of reference of the internal inquiry – set by the government – it made clear only the “findings” of the probe will be revealed.
In a statement, however, Ms Rayner said: “Boris Johnson cannot be allowed to cover-up or obscure any of the truth when he has insisted on a hugely protracted internal probe to tell him which parties he attended and what happened in his own home.”
“The Sue Gray report must be published in its entirety with all accompanying evidence,” she insisted.
Ms Rayner also claimed: “Under Boris Johnson, transparency in government has been eroded. The Conservatives have shown us how little respect they have for the rules, we’ve seen: private WhatsApp’s, missing phones, a Freedom of Information Clearing House, lost minutes of lobbying meetings – their cover-up culture has lost the trust of the British public.
“Bereaved families, our key workers and all those that diligently followed the rules have been insulted enough by the prime minister’s cover-ups and lies.”
Her call was echoed by the Liberal Democrat leader, Sir Ed Davey, who also told The Guardian: “Aside from personnel and employment issues, Boris Johnson owes it to parliament, and above all to the people, to publish this report and the transcripts in full. Anything else will be seen as the usual lies and bending of the rules.”
According to The Times, Mr Johnson and his allies are using a spreadsheet to detail the positions of MP, including those who are loyal or wavering over his leadership, with Grant Shapps, the transport secretary, said to playing a key role in the operation.
The prime minister is also expected to spend the weekend at his countryside residence, Chequers, calling MPs and trying to win them over before a possible confidence vote.
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