British Prime Minister David Cameron, seen here in 2013, repeated the "You ain't no Muslim, bruv" phrase Monday in England. Getty Images

British Prime Minister David Cameron took a hashtag and made it into a rallying cry Monday in the United Kingdom. In condemning a recent terrorist attack in London, Cameron repeated the now-famous phrase "You ain't no Muslim, bruv," which has been internationally embraced for succinctly rejecting the notion that Islam inspires or justifies violence.

"I have dedicated speeches and media appearances and sound bites and everything to this subject, but 'You ain't no Muslim, bruv' says it all, much better than I ever could," the Independent reported Cameron said. "Thank you, because that will be applauded all around the country."

The phrase first surfaced Saturday after a man with a knife attacked passers-by at the Leytonstone Tube station in London, allegedly shouting, "This is for Syria," in a possible reference to the U.K.'s involvement in airstrikes in Syria. A witness to the man's arrest took a video of the unfolding scene. "You ain't no Muslim, bruv," someone off camera yells in the clip. "You're not a Muslim, bruv. You're an embarrassment."

The phrase immediately went viral on Twitter, soon trending worldwide as a hashtag. "'You ain't no Muslim, bruv' is a wonderfully British cry of defiance," journalist Stephen Daisley wrote on Twitter. The New York Times noted some resistance to the phrase, however, because Islam forgives sinners.

Cameron, calling the attack "hideous" in a Monday statement, added that the phrase is "brilliant," the Sun reported.

The suspect in the Leytonstone attack, 29-year-old Muhaydin Mire, was charged with attempted murder. He was set to appear in court Monday, while security at train stations across the country was increased, with police dogs and undercover officers. "The safety of the traveling public remains our top priority," Assistant Chief Constable Mark Newton told the Telegraph. “In addition to our usual specialist response teams, last week we launched Project Servator, deploying even more highly visible police patrols designed to identify and deter terrorism ... following the incident last night, we are now deploying still more officers in this role."