#TrumpVsMusk Donald Trump appeared to dismiss a peace overture from his former close political ally Elon Musk on Friday, calling him someone who had “lost his mind” as the extraordinary falling out between the two men looked set to continue.

The US president and the richest person in the world – who had been tasked with slashing the federal government – fell out in spectacular fashion on Thursday in a series of escalating social media posts that roiled the political world.