The married politician was pictured kissing and embracing his adviser, with whom British tabloid The Sun alleges he is having an affair. The newspaper reported that the images were from May 6, two weeks before cross-household contact was allowed indoors in England.

"I've been to see the Prime Minister to resign as Secretary of State for Health and Social care... Those of us who make these rules have got to stick by them, and that's why I've got to resign," Hancock said in a video posted on his Twitter page.

"I'm very proud of what we've done to protect the NHS at the peak, to deliver that vaccine rollout -- one of the fastest in the world -- and I look forward to supporting the government and the Prime Minister from the backbenches," he added.

In a letter to Boris Johnson, he apologized writing, "I want to reiterate my apology for breaking the guidance and apologise to my family and loved ones for putting them through this."

The Sun's report had sparked accusations of apparent cronyism -- an allegation that the health secretary has faced previously for awarding a contract to a former neighbor for Covid-19 test kits.

Hancock has been under pressure for months over his handling of the coronavirus pandemic in Britain, but had managed to cling onto his role.
Former Chancellor and Home Secretary Sajid Javid will replace Hancock, Downing Street announced.

Hancock was accused by Prime Minister Boris Johnson's former chief adviser Dominic Cummings of botching the country's coronavirus testing program, as well as lying about the dire situation in care homes and the shortage of personal protective equipment (PPE). Hancock has denied the claims.

To date, more than 128,000 people have died in the United Kingdom from Covid-19 -- the highest death toll in Europe. One of the biggest early failures of the UK's response to Covid-19 was in building a test-and-trace system. The British government has also been criticized for neglecting care homes, allowing many facilities to go without sufficient PPE, testing and clear guidelines.

Cummings delivered a damning account of the government's coronavirus response in a marathon seven-hour hearing before members of parliament in Westminster last month, accusing Downing Street and Hancock of misleading the British public.

The divisive figure, who quit his post last November amid the UK's deadly second wave of the pandemic, doubled down on his criticisms of Hancock last week.

"As the PM said himself, Hancock's performance on testing, procurement, PPE [personal protective equipment], care homes etc was 'totally f**king hopeless,'" Cummings said in a tweet, sharing a screenshot of what appears to be a WhatsApp exchange with Johnson just days after the UK went into its first full lockdown amid a worsening outbreak.

On March 27, 2020, the same day that Johnson and Hancock both tested positive for the coronavirus, Cummings said he texted the prime minister to tell him the pace of coronavirus testing was too slow and that the health minister had misled government about his ability to speed it up.

According to the screenshot shared on Cummings' blog and on Twitter, Johnson responded: "Totally f**king hopeless."

In another text message a month later, on April 27, when National Health Service staff were running out of critical masks and gowns, Johnson said the PPE shortages were "a disaster," and suggested taking Hancock off procurement of the equipment entirely.

"Wtf do we do?" Johnson wrote.

Asked last week by Sky News whether he was indeed hopeless, Hancock said: "I don't think so." Johnson has not commented on the WhatsApp messages, and his official spokesman said the Prime Minister does not plan to engage with every allegation that is made.

The chaos around Hancock had already reached such a scale that it even drew the attention of the Queen.

The Queen alluded to the health secretary's woes on Wednesday in her first in-person audience with the prime minister in 15 months, informing Johnson that she had been speaking to "your secretary of state for health, poor man."

It is unclear whether the comment was a reaction to the heavy burden of managing the country's coronavirus response, or an acknowledgment of the criticism Hancock has received from Cummings.

"I've just been talking to your secretary of state for health, poor man. He came for privy council. He's full of ..."

"Beans," Johnson quipped.

"He thinks that things are getting better," the Queen said, to which Johnson replied: "Well, er, they are, in the sense that we're ..." before the video abruptly ends.