Gatwick chairman Sir Roy McNulty has attacked the monopoly he claims would be exerted by Heathrow if a new runway at the airport is given the go-ahead.

Gatwick and Heathrow are currently setting out their final arguments to the Airports Commission ahead of a government decision over where to build extra capacity in the UK.

Mr McNulty warned that Heathrow could be given a monopoly that would result in higher prices for passengers. 

Setting out the positive case for a new runway at Gatwick, the airport's chairman said it could boost the UK economy by as much as £40 billion.

A spokesman for Heathrow refuted the claims, however, saying: "Frontier Economics estimates that removing capacity constraints at Heathrow could cut average ticket prices by £95 today and by £300 in 2030."

The Airports Commission will publish its final report on expanding airport capacity in the UK in summer 2015, after the next general election.