Simon Clarke says ‘pipeline of future voters is dead’ as party figures warn Kemi Badenoch her job as leader is in danger

The Conservative party is fighting to justify its existence amid concerns that its pipeline of future voters is “completely dead”, a former cabinet minister and leading thinktank director has said.

Simon Clarke, an ally of Boris Johnson who backed Kemi Badenoch for the leadership last year, was among a string of former Tory ministers and serving MPs to tell the Guardian she faced removal by her party if she did not turn its fortunes around by next year’s local elections.