A personal cell phone number belonging to the UK's prime minister, Boris Johnson, has reportedly been publicly accessible online for fifteen years.
Johnson's number was listed on a think tank press release published on the internet back in 2006 when he was the Member of Parliament for the riverside town of Henley in Buckinghamshire.
The security breach was first reported by the website Popbitch in a piece headlined 'Hoping not to butt-dial Boris'.
“It’s not as though the Prime Minister’s personal phone number could just be floating out there on the internet, is it?" quipped the site.
"It would be absolutely insane if it was tacked on to the bottom of an old press release that he dished out freely while MP for Henley, and Shadow Minister for Higher Education.”
According to the BBC, the exposed number appears to still be in use by the Conservative prime minister.
Leader of the opposing Labor party Sir Keir Starmer described news of the number's availability as "a serious situation [that] carries a security risk."
Starmer said: "A lot of people will be concerned, not just about who has got the number but who has been using it."
Johnson has come in for criticism recently concerning his use of messaging apps and SMS messages after it was reported that he personally texted businessman Sir James Dyson with a promise to "fix" Dyson's tax issue.
"What has come out in recent weeks is [about] privileged access—those who can WhatsApp the prime minister for favors—and this all is further evidence that there is one rule for them and another rule for everybody else," said Starmer.
Speaking on BBC Radio 4's Today program, former national security adviser Lord Ricketts said that “hostile states with sophisticated cyber capabilities or criminal gangs" could have exploited Johnson’s number.
He added that for a prime minister to change their number after taking office is an "elementary security precaution these days."
Home Office minister Victoria Atkins said that the PM was "aware of his responsibilities" on national security and that she had "complete and utter confidence" that he and his advisors would meet those responsibilities.