Boris Johnson was more than 4,000 miles away from the political eruption that saw voters in two very different constituencies vote out the Conservatives.

Not long after learning that he had lost one Tory stronghold in Devon to the Liberal Democrats and a West Yorkshire seat to Labour, the Prime Minister was under the palm trees and in the pool of his luxury hotel in Kigali.

Any semblance of tranquillity from the 6am dip in the Rwandan capital where he is attending a summit of Commonwealth leaders would not last long.

Within the next hour, the Prime Minister would receive the shock of a phone call from his old ally Oliver Dowden who was warning him he would shortly be resigning as Tory party co-chairman, a Conservative source said.

Mr Johnson was likely still drying off from his dip when they spoke because within minutes the resignation letter was online – and contained a barb aimed at the Prime Minister.

The Tory’s 24,000 majority in Tiverton and Honiton had been replaced by a 6,000 majority for the Lib Dems and Labour had won back Wakefield, one of the seats seized by Mr Johnson as he led the Conservatives to a massive majority in 2019.

Mr Dowden published his letter to the Prime Minister online setting out that supporters were “distressed and disappointed by recent events” and that he believed “someone must take responsibility”.

It would become clear that Mr Johnson would not join his Cabinet ally in resigning and he would soon be on the phone to key ministers.

Chancellor Rishi Sunak and chief whip Chris Heaton-Harris joined the Prime Minister in a call, which the Tory source characterised as being the routine daily meeting.

Mr Johnson did not appear dented by the political blows during a round of broadcast interviews with British media at the Commonwealth Heads of Government Meeting conference centre.

He insisted he would “keep going” with the Government’s agenda and vowed to “listen” to the voters.

But there were signs of anger in the Johnson camp, with the Tory source apportioning some of the blame for the electoral losses on the “nonsense” of the media’s “endless reportage and Kremlinology of partygate”.

Asked if he feared Mr Dowden was acting as an outrider for a possible leadership challenge from someone like the Chancellor, the source said: “What do I know, but I’d be astonished if it was the Chancellor.

“The Prime Minister spoke to the Chancellor this morning as he does almost every morning.”

Mr Johnson went on to meet with the Prince of Wales amid signs of a row between No 10 and Clarence House.

The Prime Minister had suggested he would tell Charles to be open minded about the widely criticised and currently stalled policy of sending asylum seekers who arrive in the UK by unauthorised means on a one-way ticket to Rwanda.

But on the morning of their meeting, he declined to set out what he planned to say to Charles, who has reportedly described the scheme as “appalling”.

Despite the dent to his authority in the UK and the need to stem the fallout, Mr Johnson was determined to stay in Rwanda before going ahead with his trip to the G7 summit in Germany.

The source said: “To not be at the G7 would be an abdication of responsibility for any prime minister.”