On Friday I was shown a bombshell message from a senior source close to the Intelligence and Security Committee (ISC).

It said that at least one member of the committee thought it would be unlikely the Prime Minister would be able to survive the publication of the second tranche of documents relating to the appointment of Peter Mandelson.

I then spoke to someone who works alongside officials working on the release of the papers. 'I've been told the same thing,' they revealed. 'The general feeling is the documents will be terminal for the Prime Minister.'

That would explain why yesterday No. 10 took a giant shovel and suddenly announced it was burying every last one of them.

According to Darren Jones, Chief Secretary to the Prime Minister, a 'small number' of documents relating to Mandelson had suddenly materialised. These had finally been submitted to the ISC. But as a result, this had delayed the publication process, meaning none of them will now be published until after the Whitsun recess, which ends on June 1.

This was, of course, a total farce. What Jones was in fact describing seemed to be an old-fashioned – if increasingly desperate, shambolic and transparent – cover-up. As ISC member Jeremy Wright revealed to the House of Commons, the Government is now flagrantly attempting to 'redact documents for other reasons... or, in some cases, to withhold documents altogether'.

Emily Thornberry, chair of the Foreign Affairs Committee, was even more blunt. 'My Committee and the ISC are trying our best to get to the truth, and we are having obstacles put in our way,' she declared.

The reason those obstacles are being erected is blatantly obvious. They have nothing to do with the danger of prejudicing national security or offending Britain's diplomatic partners. They are about trying to prop up Keir Starmer so he can stagger through the final few weeks of his premiership.

When the Mandelson saga first unfolded, the question on everyone's lips was whether the files that were due to be released by – or rather, dragged out of – the Government would contain a 'smoking gun' to finish off the Prime Minister. And it quickly became apparent that, at least as far as Sir Keir's increasingly paranoid No.10 team was concerned, they did.

MPs first demanded the disclosure of the documents on February 4. At that time, we were told the relevant papers would be released in hours. This quickly turned into days. Then we were told the release of the documents would be staggered. A month later, on March 11, a smattering of largely irrelevant files was released. The rest of the documents would be published in advance of the local elections, journalists and MPs were told. The publication was pushed back until after those elections, but before recess. Now they are not being published until after recess.

Meanwhile, whilst the timetable was being repeatedly gerrymandered, a concerted effort was launched to 'disappear' much of the most sensitive evidence. Mobile phones were mysteriously stolen. Texts were erased via WhatsApp's 'disappearing messages' function, which deletes correspondence automatically. Entire documents vanished from Government servers.

Yesterday I spoke to a minister about what they thought was going on. They conceded that they thought some 'mundane bureaucracy' was at work.

But they also conceded political skulduggery was at play. 'If they wanted to publish 90 per cent of the documents this week, then say 'there's a little more to come', they could have done. So the question is why they have opted to make a s**t week even worse.'

The answer is the parlous political health of the Prime Minister. On Saturday, I was told by a senior cabinet minister that, despite the bombastic rhetoric of the past 24 hours, Keir Starmer has indeed decided to step down. But he is adamant that he be given the space to do so in a manner of his own choosing.

His great fear is that when the Mandelson papers are finally published, that opportunity will finally be snatched away from him. Not unreasonably. Sir Keir is now so weakened in the eyes of his vengeful party that it will no longer take a smoking gun to finish him off. A smoking pea-shooter will almost certainly do the trick.

So, as with just about every aspect of this rapidly stagnating government, paralysis has taken hold. Ministers and Labour MPs are desperate to get the Mandelson papers published, so they can absorb the final hit and move on. But the Prime Minister believes that blow – regardless of how weak or severe – will prove terminal.

So the cover-up continues. And the truth must await the slow, lingering political demise of the infirm occupant of Downing Street.