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* Heathrow, to west of London, is UK's biggest airport
* Legal battles, political wrangling have long blocked
expansion
* PM Johnson opposes expansion, spokesman says to respond
later
* Ruling comes amid COVID-induced downturn, Brexit
uncertainty
* Heathrow keen to retrieve crown as Europe's busiest hub
(Adds PM spokesman's comment, bullets)
By Sarah Young
LONDON, Dec 16 (Reuters) - Britain's top court gave the
go-ahead to the expansion of Heathrow Airport on Wednesday,
allowing the 14 billion pound ($19 billion) plan to proceed
after decades of legal battles and political wrangling.
The Supreme Court ruling overturned a previous court
decision that had blocked the plan on environmental grounds.
Heathrow, Britain's biggest airport, currently has only two
runways and is keen to proceed despite the plunge in air traffic
during the COVID-19 pandemic that has seen it lose its crown as
the busiest hub in Europe.
Prime Minister Boris Johnson has been a vociferous opponent
of the expansion, which was approved under the previous
government. As mayor of London, he said in 2015 he would lie
down in front of bulldozers if necessary to stop construction
of the third runway.
His spokesman said on Wednesday the government had noted the
court's judgment and would respond in due course.
In February, a court had declared the expansion unlawful,
ruling in favour of climate change campaigners. The judge had
said that a failure to take into account the British
government's commitments on climate change was "legally fatal"
to the plans.
But a Supreme Court judge told a virtual session on
Wednesday that the government had taken climate change
commitments into account when designing its airport policy.
"For these reasons, the Court unanimously concludes that the
appeal should be allowed. The airports national policy statement
is lawful," Judge Philip Sales said.
Since February, the aviation sector has been hit by its
worst ever downturn, meaning Heathrow now has plenty of spare
capacity, but the airport said another runway was still vital
for the future.
BREXIT
"Demand for aviation will recover from COVID-19, and the
additional capacity at an expanded Heathrow will allow Britain
as a sovereign nation to compete for trade and win against our
rivals in France and Germany," a Heathrow spokesman said in a
statement.
Heathrow and its supporters argue that Britain's departure
from the European Union makes expansion critical to ensuring the
country can increase trade with the rest of the world. The new
runway won't be opened until the 2030s, Heathrow has said.
The airport is owned by Spain's Ferrovial, the
Qatar Investment Authority and China Investment Corp, among
others.
Though it is Britain's biggest airport by value, its two
runways compare with Paris's and Frankfurt's four and
Amsterdam's six. Before the pandemic, it had no space to add new
flights.
The project has been hotly debated in Britain for almost
half a century. The new runway was previously approved in 2009
before being scrapped the following year, and then approved
again in 2018.
Wednesday's ruling represents a setback to wider hopes among
climate campaigners of using Heathrow as a test case to develop
similar legal challenges to heavily polluting transport, energy
or other projects in other countries.
Heathrow said that its expansion plan must now go through a
planning process that will require it to prove expansion is
compliant with Britain's climate change obligations before
construction can begin.
($1 = 0.7408 pounds)
(Additional reporting by Michael Holden and Kate Holton;
Editing by Alex Richardson and Gareth Jones)
