British Prime Minister Boris Johnson on Tuesday dismissed "seditious propaganda" that he has lost his vim since nearly dying of the coronavirus, challenging all-comers to a wrestling bout as he rallied his ruling Conservatives.
Johnson, 56, contracted Covid-19 and was placed in intensive care in April, crediting hospital staff with saving his life.
Since then, some Conservative lawmakers have openly speculated about his long-term health, against a backdrop of criticism about his leadership and response to the outbreak.
But in a speech to his party's virtual annual conference, Johnson -- often referred to simply by his first name or "BoJo" -- portrayed the criticism as an opposition plot.
"I have read a lot of nonsense recently about how my own bout of Covid has somehow robbed me of my mojo," he said.
"And of course this is self-evident drivel, the kind of seditious propaganda that you would expect from people who don't want this government to succeed, who wanted to stop us delivering Brexit and all our other manifesto pledges.
"I can tell you that no power on Earth was and is going to do that. And I could refute these critics of my athletic abilities in any way that they want, arm wrestling, leg wrestling, Cumberland wrestling, sprint-off, you name it."
Johnson's fighting talk has been replicated this week by US President Donald Trump. The prime minister wished Trump well when he was hospitalised with Covid last week.
The British leader conceded that his coronavirus case was seriously worsened by being overweight, but that he had since lost 26 pounds (12 kilograms).
"I am going to continue that diet, because you've got to search for the hero inside of yourself, in the hope that that individual is considerably slimmer," he said.
The British economy likewise appeared healthy before the pandemic but suffered from "chronic underlying problems", he said, such as a shortage in skills and affordable homes, and inadequate transport infrastructure.
"So we cannot now define the mission of this country as merely to restore normality, he said. "We will succeed, just as this country has seen off every alien invader for the last 1,000 years."