UK officials are monitoring social media posts by Elon Musk and others as a possible security risk. The monitoring is being carried out by a team in the Home Office's Homeland Security group, which is responsible for reducing national security risks and, according to a government website, "focuses on the highest harm risks to the homeland".

Musk's escalating criticism and mocking of European leaders and governments, which he has done repeatedly via X, the social media platform he owns, has sparked a backlash from

But the reaction to Mr Musk’s rant also reveals something about the prime minister and his principal political opponent. The most important biographical difference between Sir Keir and Kemi Badenoch,