BBC: Conservative co-chair Oliver Dowden has resigned following two by-election losses for the party to Labour and the Liberal Democrats.
The Lib Dems overturned a huge Tory majority in Tiverton and Honiton, Devon, their third by-election victory over Boris Johnson's party in a year.
And Labour retook the seat of Wakefield, West Yorkshire, which it lost at the 2019 general election.
The prime minister said he would "keep going" and address people's concerns.
In a letter to Mr Johnson, Mr Dowden said Tory supporters were "distressed and disappointed".
He wrote: "We cannot carry on with business as usual. Somebody must take responsibility and I have concluded that, in these circumstances, it would not be right for me to remain in office."
Mr Dowden also called his resignation "a deeply personal decision that I have taken alone" following a "run of very poor results for our party". With video » | Justin Parkinson, Political reporter, BBC News | Friday, June 24, 2022
A kick up the arse is what you needed and a kick up the arse is what you’ve been given. And deserved! Now it’s time to dust down the bike in your shed and get on it!
Just to get you into Number 10, I, and millions of others, have had to relinquish all our rights as a European citizens. And what a mess you’re making of the job!
You have written about Churchill a lot and you have identified with him; but I can assure you of one thing: you are no Winnie!
In these election results, you have got what you deserve: defeat. – © Mark Alexander
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Conservatives Lose 2 Races in U.K., Adding to Pressure on Boris Johnson: The double defeat exposed the party’s vulnerabilities and was likely to revive talk of another no-confidence vote against the prime minister. »
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