Donald Trump has branded London Mayor Sadiq Khan "a disaster" in the wake of the latest wave of violence in the city, which saw three men killed in separate attacks in less than 24 hours.
Two teenagers were murdered within minutes of each other in different parts of the capital on Friday, while a man was stabbed to death on Saturday afternoon.
The US President retweeted a post by Katie Hopkins about the violence, adding: “LONDON needs a new mayor ASAP. Khan is a disaster - will only get worse!”
Hopkins had shared news articles about the incidents with the words: “20 hours in Stab-City UPDATE 2 stabbed to death 1 shot dead Three stabbed - but not dead. Wandsworth & Tower Hamlets This is Khan's Londonistan."
An 18-year-old boy was stabbed to death in Wandsworth on Friday afternoon, minutes before another 19-year-old man was fatally shot in Plumstead.
Hours later, a man in his 30s was killed in Tower Hamlets, east London and three men were also stabbed in a separate attack in Clapham.
The Metropolitan Police said 14 people - including several boys and a girl - have been arrested in connection with the incidents in Wandsworth, Plumstead and Clapham.
Mr Trump didn’t leave it at one tweet, later commenting on a post that said: “Khan is the reason I don’t feel like visiting London anytime soon.”
He shared the tweet, adding: “He is a national disgrace who is destroying the City of London!”
A spokesman for Sadiq Khan said: "Sadiq is focusing on supporting London's communities and over-stretched emergency services.
"He has been in regular touch with senior Met police officers last night and throughout the day.
"His thoughts are with the victims' families. He is not going to waste his time responding to this sort of tweet."
Labour leader Jeremy Corbyn also weighed in on the clash, condemning both Donald Trump and Katie Hopkins.
He tweeted: “Absolutely awful to see @realDonaldTrump using the tragedy of people being murdered to attack the Mayor.
“@SadiqKhan is rightly supporting the police to do their job while Katie Hopkins spreads hateful and divisive rhetoric. They seek to divide at a time we need to come together."
It is not the first time the US president and Mayor of London have clashed.
Mr Trump branded Mr Khan a "stone cold loser" in a two-part tweet as he touched down for his state visit to Britain on June 3.
The Labour mayor then accused the president of "playground behaviour" and claimed he was a "poster boy" for the far-right.