Sajid Javid, the former chancellor and home secretary, will succeed Matt Hancock as UK Health Secretary, according to Downing Street.
The appointment occurred a day after video evidence of Mr Hancock kissing an aide in his ministerial office in violation of coronavirus regulations surfaced.
Last month, images and video surfaced of Mr Hancock hugging assistant Gina Coladangelo, and the former Health Secretary was under increasing pressure to resign, which he finally did on Saturday when he handed Boris Johnson his resignation.
“The last thing I would want is for my private life to distract attention from the single-minded effort that is driving us out of this crisis,” Mr Hancock wrote in a letter to British Prime Minister David Cameron.
“I want to reiterate my apology for breaking the guidance, and apologise to my family and loved ones for putting them through this. I also need to be with my children at this time.”
He said: “We owe it to people who have sacrificed so much in this pandemic to be honest when we have let them down as I have done by breaching the guidance.”
He praised NHS employees and officials from the Department of Health and Social Care (DHSC), but confessed that "we didn't get every decision right."
But he said: “I know people understand how hard it is to deal with the unknown, making the difficult trade-off between freedom, prosperity and health that we have faced.”