MPs joined hundreds of protesters on Saturday to object to a planned extension to Heathrow Airport.

Those attending the No Third Runway rally at Parliament Square included Labour and Conservative mayoral candidates Sadiq Khan and Zac Goldsmith, as well as shadow chancellor John McDonnell.

Mr McDonnell, also MP for Hayes and Harlington, said in a speech at the rally: “In my constituency at the moment, people are literally dying.

“They are dying because the air has already been poisoned by the aviation industry.”

The event has been trending on both Twitter and Facebook under the hashtag #NoThirdRunway.

Robert Barnstone, 22, campaign organiser at Heathrow Association for the Control of Aircraft Noise, told the Hillingdon Times: “The event sent an excellent message to London and to the voting public.

“This is by no means the last of this.”

London mayor Boris Johnson, also MP for South Ruislip and Uxbridge, was unable to attend the event because of a prior arrangement.

Mr Barnstone said the mayor had extended his apologies and said he was "Still committed to the cause and there in spirit".

Protestors chanted: “No ifs, no buts, no third runway” in a call back to David Cameron’s 2009 promise to not allow the extension to go ahead.

The prime minister is due to respond to the proposal in November.

Pictures courtesy of Robert Barnstone of HACAN, with thanks