Boris Johnson’s WhatsApp messages from the first year of the pandemic are missing from evidence handed to the Cabinet Office due to a “security breach”.

It is understood the breach refers to the discovery at the end of April 2021 that the then-PM’s phone number had been freely available online for 15 years.

As a result, a phone containing messages from May 2021 onwards has been handed to the Cabinet Office to assess, but no messages prior to this date are yet available.

WhatsApp messages sent by Johnson to the Cabinet Office on Wednesday are “being reviewed for national security sensitivities and unambiguously irrelevant material and appropriate redactions are being applied,” Ellie Nicholson, the co-director of the Cabinet Office’s Public Inquiry Response Unit, wrote in a witness statement made public today.

“In that material, there are no WhatsApp communications before May 2021. I understand that this is because, in April 2021, in light of a well-publicised security breach, Mr Johnson implemented security advice relating to the mobile phone he had had up until that time.

“It is my understanding that Mr Johnson has possession of that device, and that it is a personal device. On 31 May the Cabinet Office spoke to Mr Johnson’s legal representatives to ask them to check with Mr Johnson that he has possession of the phone, and to confirm this to the Cabinet Office. The Cabinet Office explained that if the phone could be passed to the government it could be assessed by security experts.

“On the morning of 1 June, the Cabinet Office emailed to chase for a response. We have not yet received a substantive response. As the Cabinet Office is not, I understand, in possession of the phone, any material stored on the phone is not in the Cabinet Office’s possession or control.”

The revelations come as the department launches a judicial review against the official Covid-19 inquiry after its chair, Heather Hallett, demanded unredacted evidence be handed over.

At 4pm on Thursday, which was the deadline for providing the inquiry with its evidence, the Cabinet Office served the inquiry with notice of a legal challenge to its request for documents.

In a letter, the department told the inquiry of its intention to bring the judicial review.

“We do so with regret and with an assurance that we will continue to cooperate fully with the inquiry before, during and after the jurisdictional issue in question is determined by the courts.”

Following the notice, the inquiry put out the following statement: “At 16.00 today the chair of the UK Covid-19 public inquiry was served a copy of a claim form by the Cabinet Office seeking to commence judicial review proceedings against the Chair's Ruling of 22 May 2023. Further information will be provided at the Module 2 preliminary hearing at 10.30am on Tuesday 6 June.”

Last week, Cabinet Office officials refused to hand over Whatsapp messages, diaries taken by Johnson during the pandemic, and notebooks that the inquiry has been told contain contemporaneous notes. openDemocracy has already spent more than a year fighting the Cabinet Office over the release of Johnson’s ministerial diaries from the peak of the pandemic, alongside those of other ministers.

Susie Flintham, a spokesperson for Covid-19 Bereaved Families for Justice, said: “If Boris Johnson fails to hand over his relevant communications to the inquiry he needs to face the full force of the law. His latest claim that he conveniently replaced his phone the same month that he announced the inquiry is as pathetic and shameful as the lies he told about breaking his own lockdown rules."

"After failing families like mine so badly in the first instance, he has lied to us repeatedly and each time poured salt in our wounds and shown callous disregard to the people of this country. It’s time for him to face the consequences of his actions, and that means criminal charges if he can’t provide the inquiry the evidence it needs.”

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