The race has been mooted for years, in addition to a British Grand Prix on the schedule, with London Mayor Sadiq Khan saying he was keen on the prospect of a race in the capital.
Horner’s opposite number at Mercedes, Toto Wolff, has already put pressure on Khan and Prime Minister Boris Johnson to get behind the London race — and Horner said: “It would be fantastic to do a London Grand Prix.
“We saw from the event in Trafalgar Square a few years ago the appetite for F1 and it showed it is possible to close central London down to hold an event.
“It would be a fantastic advert for London and great to see and hear GP cars around the streets. As with all these things it’s never straightforward. The most important thing is the desire for it.
“If the Mayor wants it to happen, if the Government wants it to happen and Formula One wants it to happen, hopefully there’s enough intent that it’s not unfeasible.”