UK lawmakers set to decide on Heathrow expansion

British lawmakers are set to vote on whether to expand Europe's biggest airport the most important transportation decision in a generation, according to the Government.

Today's decision on a third runway at Heathrow airport comes after years of debate, and approval of the 14 billion-pound (USD 18.6 billion) project is certain to be challenged in the courts.

Prime Minister Theresa May has directed Conservative Party lawmakers to vote for the project.

Foreign Secretary Boris Johnson, one of the most vocal critics of Heathrow expansion, won't participate because he is on a trade mission abroad.

Opponents object to the project on environmental, noise and financial grounds. Friends of the Earth says it is "morally reprehensible" and would see the enlarged Heathrow emitting as much carbon as the whole of Portugal.