Trump was widely criticised for his tweet which grossly misrepresented Khan's words - what he'd actually said was:
Londoners will see an increased police presence today and over the course of the next few days.
There’s no reason to be alarmed. One of the things the police and all of us need to do is ensure that we’re as safe as we possibly can be.
Instead of sinking to his level, Khan hit back in the best way - by not feeding the troll.
A spokesperson for the Mayor said:
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.
Press Association reports that in a speech addressing police funding Khan noted that London has other responsibilities:
From major events, there's a big cricket match today, to state visits - some welcome, some less so.
But the fact is we need to make sure the police have the resources and support they need, and as the mayor my job is to make our city safe and I'll do my best as the mayor to be an advocate and champion for our police to get the tools they need.
The shade is subtle, but it's certainly there.
Of course, this seems to have not gone down well with the President.
Again. Donald Trump took the quote out of context.
Now he's being called out on the fact that he did it, he's clearly trying to pivot the narrative to whether you can trust the press.
Because this is apparently how diplomacy works among political leaders of allied countries.