US President Donald Trump is known to have a long-running feud with the incumbent Mayor of London: Trump earlier blamed him for the rise in knife crime in the UK capital, while Khan branded the POTUS as a "poster boy for racists".

Donald Trump has torn into Sadiq Khan once again by suggesting that the London mayor had something to do with the recent hacking of the Metropolitan Police's social media account.

The US president quote-tweeted Katie Hopkins, a right-wing British political commentator and former reality star, who said the Met Police had “lost control of London streets” and “of their Twitter account”.

Trump added: “With the incompetent Mayor of London, you will never have safe streets!”

With the incompetent Mayor of London, you will never have safe streets! https://t.co/pJqL1NjyvA — Donald J. Trump (@realDonaldTrump) 20 июля 2019 г.

On Friday night, the Twitter account and website of London’s Metropolitan Police were targeted by anonymous hackers, who posted a series of unusual messages and emails to subscribers on behalf of the Met’s press bureau.

One of the tweets read "F*** the police", while another linked to a fake press release demanding freedom for Digga D, a young rap artist jailed last year for conspiracy to commit violent disorder. He was caught along with several members of a gang armed with machetes and baseball bats who were on their way to a battle with rivals.

The Metropolitan Police said the hackers did not affect its IT infrastructure and only gained “unauthorised access” to its MyNewsDesk account, which it uses to post news updates on Twitter and website, as well as send emails to subscribers.

We are aware that the @metpoliceuk has been subject to unauthorised access and our media team are working hard to delete the messages and ensure the security of the account. Please ignore any Tweets until we verify that it is back under official control. RT — Supt Roy Smith (@roysmithpolice) 19 июля 2019 г.

The bizarre messages have since been deleted.

Trump has in the past called out Sadiq Khan over the security situation in London, referring to him as a “national disgrace” and a "stone cold loser who should focus on crime in London”.

Khan, in turn, compared the president to a “20th century fascist” and called him a "poster boy for racists".

Knife crime, burglary and robbery have reportedly soared in London since Sadiq Khan became mayor in 2016, and he has been accused by critics for not doing enough to ensure security in the capital. Khan, meanwhile, blamed growing violence on the Tory government-imposed austerity policies.