President Donald Trump abruptly ended his White House news conference on Monday after combative exchanges with two reporters. Weijia Jiang of CBS asked Mr Trump why he was placing so much emphasis on the amount of coronavirus tests that have been conducted in the United States. The exchanges came after Mr Trump insisted his administration had “met the moment” and “prevailed” on coronavirus testing, even as the White House itself became a symbol of the risk facing Americans by belatedly ordering everyone who enters the West Wing to wear a mask.