trump-winUS President Donald Trump has raised security concerns as he urged world leaders to call him on his cellphone instead of using official channels of communication.

Officials said leaders of Canada, Mexico and France were given his personal mobile number, with Canadian Prime Minister Justin Trudeau having reportedly called him on the line. According to French officials, French President Emmanuel Macron and Trump also exchanged numbers, but there have been no reports of the leaders having used the line.

Communications between world leaders usually take place through official channels that are deemed secure and are subject to careful coordination between the countries involved.