Trump reportedly inviting world leaders to call his cell

President Donald Trump's use of cell phones is raising security concerns again.

The president has been giving his mobile phone number to world leaders and urging them to call him directly, the Associated Press reported Tuesday. Trump has given his number to the leaders of Canada, France and Mexico, but so far only Canadian Prime Minister Justin Trudeau has used the number, according to the report.

The report notes that while such a practice breaks with security protocol, it also raises concerns about the security and secrecy of the president's communications. Presidents generally place calls on secure phone lines, and even though use of mobile communications devices is pretty ubiquitous these days, they are still vulnerable to eavesdropping, national security experts warn.

Trump's phone use has raised national security questions before. The Secret Service issued Trump a secured phone for his inauguration, but the president has since reportedly used an unsecured Android phone to tweet from the White House while watching television.

Security experts have said a smartphone given to a president would have extremely limited uses.

"It's not really good for much," Larry Johnson, who worked at the Secret Service from 1982 to 2006, told CNET in January. "You can't make a phone call, because it's too easy to be intercepted.

"I can scare you with how easy it is," he said.

Trump's reported use of an unsecured phone came after an election filled with hacks of the personal communications of Democratic political figures and organizations.

The White House didn't immediately respond to a request for comment.

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