One Briton has been injured in suspected terror attacks in Brussels.
At least 26 people have been killed in two explosions at the Belgian capital's airport and one at a Metro station in the city, with as many as 136 wounded.
And Downing Street officials confirmed at least one British citizen was among those hurt.
London mayor Boris Johnson had previously said."It looks as though there may be one UK casualty... though the details on that are very sketchy at the moment."
Speaking to Sky News, he said he was not aware of any suggestion the explosions could indicate any associated threat to London.
"The most important thing to get across is that we know of no reason to think that there is any read-across from what's happened in Brussels to events here in this city," he said.
"We have no intelligence to suggest there is any immediate threat but as a precaution and for the purposes of reassurance, there has been a stepping up of the presence of police at major airports."
He added: 'We must show maximum possible solidarity with the people of Brussels and the people of Belgium."
