Leadership uncertainty will risk UK security while Boris Johnson is incapacitated, warns former defence minister

'We must anticipate adversaries attempting to exploit any perceived weakness'

The UK’s security will be at risk unless the government quickly clears up confusion about who is in charge in Boris Johnson’s absence, a former Tory defence minister says.

Tobias Ellwood raised the alarm after Michael Gove refused to discuss who had the authority to press the Trident button if the country came under nuclear attack.

Asked if Dominic Raab, Mr Johnson’s de-facto deputy, had the power, Mr Gove replied: “I simply can’t talk about national security matters” – as he argued key decisions would be made “collectively”.

But Mr Ellwood, the defence minister until 2019, tweeted: “It is important to have 100 per cent clarity as to where responsibility for UK national security now lies.

“We must anticipate adversaries attempting to exploit any perceived weakness.”

Mr Ellwood – a former captain in the Royal Green Jackets – was reacting to Mr Gove’s morning interviews, in which he gave an update on the prime minister’s condition, in intensive care with coronavirus.

“The prime minister always remains the prime minister,” the cabinet office minister told BBC Radio 4’s Today programme, adding that the cabinet would take crucial decisions by consensus.

Asked where power lay if the UK suffered a nuclear attack, Mr Gove said: “I simply can’t talk about national security matters. There are well developed protocols which are in place and which have been tested robustly over time.”

However, later, the prime minister's spokesman said Mr Raab did have the power – with the agreement of the cabinet – to take the UK to war if it was deemed necessary, even a nuclear conflict.

“The first secretary of state [Mr Raab] and the cabinet have the authority and ability to respond in the prime minister’s absence,” he said.

General Sir Nick Carter, the chief of the defence staff, expressed confidence there is a “clear” chain of command for the armed forces, while the prime minister remains in intensive care.

“We work straight through to the prime minister,” he told BBC Radio 4’s Today programme.

“But, of course, there’s the National Security Council (NSC) that’s wrapped around him and formed of many of the cabinet ministers and supported by the national security adviser.

“I think on that basis we’re pretty confident it’s business as usual as far as the operations are concerned.”

The early indications are that Mr Johnson’s condition has not deteriorated since the dramatic announcement, at 8.10pm, that he had been moved into intensive care.

Two-thirds of patients in such care have required ventilation in the first 24 hours – a process requiring heavy sedation, which would put the prime minister out of action for many days.

Although Mr Raab is the effective deputy prime minister, the post – in the absence of a written constitution – is widely seen as ‘first among equals’, rather than granting full power.

Bob Kerslake, a former head of the civil service, suggested the cabinet would have to decide who would formally take over, if Mr Johnson failed to recover quickly.

“If the prime minister was unable to continue, the Conservative Party may have to choose a new leader,” he suggested.