Even as Mr Musk was speaking, workers at USAID ’s headquarters in Washington were being told not to come in the next day. Some 600 of the agency’s staff seem to have been locked out of their emails. That followed a weekend in which the agency’s website went offline;

Elon Musk is only one week into his role in President Donald Trump’s new administration, but the US federal government is already rolling out the Twitter playbook to manage its spending and personnel.