(Corrects passenger numbers in last paragraph)
* Johnson vowed to lie down in front of bulldozers
* Heathrow CEO: political reality has changed after 2018 vote
* Fresh legal challenge won't change timeframe for expansion - CEO
By Alistair Smout
LONDON, July 23 (Reuters) - The boss of London's Heathrow Airport said on Tuesday that construction of its new runway would go ahead despite incoming Prime Minister Boris Johnson's long-standing opposition to the expansion of Britain's biggest airport.
Johnson, whose west London constituency is near the airport, pledged in 2015 to lie down in front of the bulldozers to stop construction of a third runway at Heathrow.
"Things have moved on a long way since he made those comments," Heathrow Chief Executive John Holland-Kaye told Reuters, adding he was not worried about a change of policy under the new prime minister.
"We've had the government decision and then the vote in parliament by 4 to 1. This is now political reality - it's the will of parliament and so we're getting on with it."
Lawmakers voted strongly in favour of building a new runway in June 2018, paving the way for the airport's expansion after decades of delays and policy U-turns.
Johnson missed that vote as he was in Afghanistan on a trip as Foreign Secretary. His critics questioned the timing of the visit.
In May, the High Court in London rejected a legal challenge by environmentalists and local councils to block the expansion. Johnson said the judgment was "not the end of the story" and that Heathrow had "a long way to go before they can meet the environmental standards demanded by law".
Campaigners will renew their legal challenge against expansion after they won the right to appeal the May judgment on Monday.
Holland-Kaye said the legal challenge did not affect the timetable for expansion, which is expected to open in 2026.
"We're very confident," he said. "We're not surprised that there should be leave to appeal, given that this is an important issue.
"We are cracking on and making this happen... It doesn't change anything. It's all part of our timetable."
Holland-Kaye spoke after Heathrow, which is owned by Ferrovial, Qatar Investment Authority and China Investment Corporation among others, posted first-half revenues up 4% with a record 38.8 million passengers flying from the hub.
(Editing by Stephen Addison)
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