US President Donald Trump has seized on the government shutdown to reshape the federal workforce and punish detractors by threatening mass firings of workers and suggesting “irreversible” cuts to programmes important to Democrats.

Rather than simply furlough employees, as is usually done during any lapse of funds, White House press secretary Karoline Leavitt said layoffs were “imminent”. The Office of Management and Budget announced it was putting on hold roughly $18 billion of infrastructure funds for New York’s subway and Hudson Tunnel projects in the hometown of the Democratic leaders of the US House and Senate.