Donald Trump has criticised the mayor of London, hours after seven people were killed and 48 injured in a terror attack in the centre of the city.

“At least 7 dead and 48 wounded in terror attack,” the president wrote on his personal Twitter account, “and Mayor of London says there is ‘no reason to be alarmed!’”

In another tweet, Trump wrote: “Do you notice we are not having a gun debate right now? That’s because they used knives and a truck!”

He added: “We must stop being politically correct and get down to the business of security for our people. If we don’t get smart it will only get worse.”

In response, a spokesman for Sadiq Khan said the mayor had “more important things to do than respond to Donald Trump’s ill-informed tweet that deliberately takes out of context his remarks”.

“The mayor is busy working with the police, emergency services and the government to coordinate the response to this horrific and cowardly terrorist attack and provide leadership and reassurance to Londoners and visitors to our city.

“He has more important things to do than respond to Donald Trump’s ill-informed tweet that deliberately takes out of context his remarks urging Londoners not to be alarmed when they saw more police – including armed officers – on the streets.”