Boris Johnson, who was the British prime minister during the height of COVID, on Friday offered to hand over all his unredacted WhatsApp messages to the public inquiry set up to investigate the government’s handling of the pandemic.

The latest move further complicates matters as it bypasses the Rishi Sunak-led government’s decision to seek a judicial review into inquiry chair Baroness Heather Hallett’s order for all such messages to be handed over.

After missing a deadline on Thursday for the handover of the documents which include Johnson's messages, the UK Cabinet Office said in a statement that government officials should not be required to provide material that is “irrelevant”.

"While I understand the government's position, I am not willing to let my material become a test case for others when I am perfectly content for the inquiry to see it," said Johnson in a letter addressed to Baroness Hallett.

The 58-year-old former prime minister said he was handing over "all unredacted WhatsApps” he provided to the Cabinet Office and said he has asked it to hand over his notebooks, which he no longer has access to.

He also said that he would "like to do the same with any material that may be on an old phone, which I have previously been told I can no longer access safely".

Johnson says he has asked the government for help to turn on the device securely to hand over the material.

It relates to security concerns raised during his time as prime minister after it emerged that the particular phone number had been freely available on the internet for 15 years, which led to him acquiring a new phone.

The Opposition Labour Party has accused the government of a cover-up over its refusal to hand over all the messages demanded by the public inquiry.

The UK Cabinet Office has insisted that it is "fully committed" to its obligations to the inquiry, but that it was "firmly of the view that the inquiry does not have the power to request unambiguously irrelevant information that is beyond the scope of this investigation".

"It represents an unwarranted intrusion into other aspects of the work of government. It also represents an intrusion into their legitimate expectations of privacy and protection of their personal information," the Cabinet Office said in its letter to the inquiry.

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