Boris Johnson should not be written off, a former close aide to the departing British prime minister said on Sunday.
Lord Edward Lister suggested Mr Johnson could make a return to high office one day despite being forced from power.
Following months of scandal, Mr Johnson was forced to announce his resignation in July.
He will hand over power on Tuesday after the governing Conservative Party names its new leader on Monday.
Liz Truss, the current foreign secretary, is widely expected to win the leadership contest and succeed Mr Johnson, taking on challenges including what is forecast to be a long recession, double-digit inflation and industrial unrest.
Asked whether Mr Johnson could return to power, Lord Lister, who has been a close adviser for years and was briefly chief of staff at Downing Street in 2020-21, told Sky News: “Well, maybe in the future, I'd never say never on anything with Boris Johnson — anything is possible.
“He is going to be watching all this and if something happens in the future, as you said, if the ball comes loose in the scrum, then anything could happen. I am not going to predict. All I am saying is I would never write him off.”
Boris Johnson's final week in office — in pictures
Mr Johnson, 58, who has been in office since July 2019, has said he will continue as a member of parliament after he steps down, promising loyalty to his successor. But many will be watching to see whether he will cause problems for the new prime minister by trying to assert his will.
Asked at a news conference last week what kind of former prime minister he would be, Mr Johnson said: “Only time will tell … My intention and what I certainly will do is give my full and unqualified support to whoever takes over from me and otherwise, really to get on with life.”
Mr Johnson's advisers have been guarded over his plans, saying little more than he will continue his duties as an MP and will no longer be “public property”.
Boris Johnson's final PMQs: Most memorable moments — video
Boris Johnson's final PMQs: Most memorable moments
But he faces an investigation into whether he misled parliament with his comments on “partygate” — Covid-19 lockdown-breaking events at his Downing Street office and residence.
That could mean more details from the sometimes alcohol-fuelled Downing Street parties — potentially a thorn in the side for the new prime minister, who will want to try to restore trust in the office.
