London  - The British government approved the construction of a third runway for London's Heathrow Airport, a controversial decision likely to trigger protests from environmentalists, a news report said Thursday.

Ministers gave the go-ahead the project, which is backed by many businesses and unions, saying it will create jobs and improve Heathrow's competitiveness, the BBC reported, adding that the Labour government was to officially confirm the decision later in the day.

Critics, including residents, environmentalists and Labour lawmakers, said the project would damage Britain's credentials on fighting climate change.

The Conservative Party, which is strongly opposed to the plan, said it would overturn the decision if it was to win the next elections.

The runway, which is unlikely to be completed before 2019 would increase the number of flights to and from Heathrow from about 480,000 to 702,000 per year, the BBC said.

Heathrow, the largest of five airports sevicing the British capital, is suffering from chronic congestion and frequent flight delays. (dpa)