BORIS Johnson's former top aide in Downing Street has revealed he has a "crucial historical document" that reveals Covid decision-making at the start of the pandemic.

Dominic Cummings has threatened to auction off the document which he says is the only copy in a threat to the Prime Minister.

In a now-deleted tweet, Cummings said: "I've got the only copy of a crucial historical document from covid decision-making."

The National:

He left it up to his followers to decide on what to do with the document, giving them three options of putting it on his blog, give the document to Westminster's Joint Health and Science Committee ahead of a hearing next week, or auctioning it off as an NFT (non-fungible token) with proceeds to be given to a Covid families charity.

Cummings deleted the tweet that included the poll as there were only two options available to vote on.

An NFT is a digital version of something that uses blockchain technologies, usually with the cryptocurrency Ethereum. 

READ MORE: Twitter reacts in disbelief as Dominic Cummings sings praises of Covid lockdowns

Cummings, who is due to give evidence to MPs on the Covid response on May 26, was also critical of the UK Government's handling of the pandemic in a thread on Twitter.

Having left Downing Street in November following a behind-the-scenes power struggle, Cummings decried the secrecy of the Tory administration in relation to the Covid crisis.

He said that one of the "unarguable lessons" from February-March 2020 was that secrecy "contributed greatly to the catastrophe", adding that openness to public scrutiny would have exposed errors by the Government weeks earlier than actually happened.

Cummings added that the Government could have made their vaccine plans "99% public without risks" to the likes of national security which he said is "almost totally irrelevant to the critical parts of the problem".

He then condemned what the Tories described as a "world class" Covid plan as "part disaster, part non-existent" and called on MPs to force the Government to publish of current vaccine/variant plans and "require mostly open review of other contingency plans before we find out the hard way they're as 'world class' as the covid plan".

He described a "cultural hostility to openness" from Whitehall that has created a barrier to key groups like SAGE (Scientific Advisory Group for Emergencies).

Cummings concluded with a jab at the public inquiry the UK Government has set up into the Covid crisis saying it will be all about "relatively surface errors".

He went on: "If [they] wanted to 'learn' there wd already be a serious exercise underway. The point of the inquiry is the opposite of learning, it is to delay scrutiny, preserve the broken system & distract public from real Qs, leaving the parties & senior civil service essentially untouched."