Britain has given Heathrow Airport the green light to build a new $US22 billion ($A29 billion) runway, ending 25 years of indecision with a plan to boost the country's global trade ambitions following the vote to leave the EU.
The Department of Transport confirmed the decision and the Transport Minister Chris Grayling will make a statement to the House of Commons later on Tuesday.
Expanding airport capacity in the southeast of England has been a political hot potato for many years.
Although Heathrow has always been the favourite among businesses, it has attracted the most opposition from MPs with constituencies near the airport or under flight paths.
Heathrow, Europe's busiest airport, has been battling with its smaller rival Gatwick for the right to expand, after successive governments failed to make a decision on a new runway due to environmental and political protests.
The government said in its statement on Tuesday that it was proposing legally binding noise targets to provide respite for local residents, many of whom oppose expansion due to worries over noise and air pollution.
The project is now likely to face legal challenges and a final vote by MPs in a year's time, meaning the runway can only open by 2025 at the earliest.
"The government's preferred scheme will be subject to full and fair public consultation," Grayling said in his statement.
Grayling told reporters the government's decision is the clearest sign that Britain is open for business following its vote to leave the European Union.
"This is a really big decision for this country but it's also the clearest sign post the referendum that this country is very clearly open for business," he said.
Asked about disagreements within the government on the choice of Heathrow, which is opposed by Foreign Secretary Boris Johnson among others, Grayling said it would be impossible to deliver such a project without some people disagreeing.
Prime Minister Theresa May told London's Evening Standard newspaper the move showed the government was willing to "take the big decisions".
"Airport expansion is vital for the economic future of the whole of the UK ... Businesses will know that we are building the infrastructure they need to access global markets," the newspaper quoted her as saying.
"This decision demonstrates that as we leave the EU we can make a success of Brexit and Britain can be that open, global, successful country we all want it to be."
But Mayor of London Sadiq Khan has vowed to continue his opposition to the project.
"The government are running roughshod over Londoners' views - just five months ago I was elected as mayor on a clear platform of opposing a new runway at Heathrow," Khan said in a statement.
"I will continue to challenge this decision and I am exploring how I can best be involved in any legal process over the coming months."
