Downing Street has insisted Prime Minister Boris Johnson did not intervene in the Newcastle takeover saga amid reports he was asked to by Saudi Arabia's Crown Prince Mohammed Bin Salman.

A Daily Mail report has claimed Bin Salman, chairman of the Middle East state's Public Investment Fund, the 80 per cent majority partner in a consortium which agreed a deal to buy the club in April last year, urged the British Government to help remove stumbling blocks in the £300million-plus sale, which collapsed in July.

However, the Prime Minister's official spokesman denied he had done so and said he had asked long-standing aide Lord Udny-Lister to simply check on the progress of the talks.

The spokesman told reporters: "This was a commercial matter for the parties concerned and the Government was not involved at any point in the takeover talks on the sale."

Pressed on whether Mr Johnson played any part, the No 10 official replied: "No, the Prime Minister didn't intervene. The Government was not involved at any point in the takeover talks."

Asked whether media reports on the matter were wrong, the spokesman added: "The Prime Minister asked Lord Lister to check on the progress of the talks as a potential major foreign investment in the UK.

"He didn't ask him to intervene."

Kate Allen, the UK director of human rights organisation Amnesty International, said in a statement released to the PA news agency that the Mail report illustrated the takeover was "always more than just a commercial transaction" and that in reality it was an attempt by the Middle East state to "sportswash" its reputation.

Allen said: "The bid to buy Newcastle was a blatant example of Saudi sportswashing, so it's worrying that the prime minister would accede in any way to pressure from the crown prince over the deal.

"Reports that Mohammed Bin Salman made threats about possible damage to UK-Saudi relations if the deal didn't go ahead only illustrates that this was always more than just a commercial transaction within the football world.

"At the time that the crown prince was putting this pressure on No 10, the world was still reeling from the fall-out over Jamal Khashoggi's murder, Saudi human rights activists like Loujain Al Hathloul were languishing in jail, and Saudi warplanes were indiscriminately bombing Yemen.

"This whole tangled affair only underlines how there needs to be a proper overhaul of the Premier League's owners' and directors' test to provide proper human rights scrutiny of who is trying to buy into the glamour and prestige of English football."

The Mail reported Bin Salman had privately urged Johnson in June to reconsider the "wrong conclusion" reached by the Premier League over the deal, and that Johnson then asked Lord Udny-Lister to investigate.

"We expect the English Premier League to reconsider and correct its wrong conclusion," the prince is said to have warned the Prime Minister.

The claim comes after Johnson this week ordered a review into the collapse of the financial firm Greensill Capital amid concern over former Prime Minister David Cameron's lobbying on its behalf.

In a message to his private office, Johnson said: "One for Sir Edward" – a reference to Lord Udny-Lister, who had not been ennobled at the time.

Lord Udny-Lister reportedly told the Prime Minister: "I'm on the case. I will investigate."

Lord Udny-Lister told the Mail: "The Saudis were getting upset. We were not lobbying for them to buy it or not to buy it. We wanted (the Premier League) to be straightforward and say 'yes' or 'no', don't leave (the Saudis) dangling."

The PA news agency understands sportswear magnate Ashley is privately pleased by both the Mail report, and the emergence of an email chain between Government departments and the Premier League as it carried out its owners' and directors' tests last summer which has been published by the Evening Chronicle, as he seeks transparency over the affair.

The Premier League has declined to comment on the Mail and Evening Chronicle reports.

The PIF teamed up with Amanda Staveley's PCP Capital Partners and the Reuben Brothers to reach agreement with Ashley in a move which was greeted with delight on Tyneside, and then submitted the details to the Premier League to seek approval via its owners' and directors' test.

However after 17 weeks of deliberation, during which Ashley is understood to have been repeatedly briefed that there were "no red flags", the governing body had not made a decision either way and the consortium formally withdrew its offer.

A furious Ashley, who is waiting for an ongoing arbitration process to reach the hearing stage, believes there are questions to be answered with the email exchanges between Whitehall and the Premier League suggesting that at one point a decision might have been just days away.

The businessman bought the Magpies for £134.4million in 2007, but has been trying to sell it for much of the time since and as far as he is concerned, a deal which he believes could give the club the spending power he has been unable to provide has been done.

Supporters' anger has mounted since the takeover's apparent collapse, sparking claims – denied by Premier League chief executive Richard Masters in a letter to Newcastle Central MP Chi Onwurah in August – that rival clubs had objected to its approval.