Image copyright Reuters Image caption The independent Davies Commission has recommended expanding Heathrow, but with severe environmental restrictions

Heathrow Airport has promised to reduce night flights and curb both noise and pollution if it is allowed to build a new, third runway.

The pledge comes ahead of a government decision expected this summer on whether to expand Heathrow or Gatwick.

Last year, the Davies Commission recommended expanding Heathrow, but with strict environmental restrictions.

But, Gatwick Airport is still fighting, saying it remained the "only expansion plan that could deliver for the UK".

Heathrow said it will allow a longer quiet period overnight, with flights not allowed to land between 11pm and 5:30am, from their current 11.30pm finish and 4.30am start.

John Holland-Kaye, chief executive at Heathrow Airport Holdings, said they would bring in the new times in six and half years time if they were granted the right to expand.

The offer differs from the recommendations made by Sir Howard Davies' inquiry, which wanted a ban on night flights between 11.30pm and 6.00am.

The airport is promising to meet his calls for limits to overall noise and guarantees that local pollution would not get worse.

Heathrow supported the introduction of an independent noise authority and pledged not to add new capacity unless the airport complied with EU air quality limits.

No guarantee

John Stewart, chair of the anti-noise group HACAN ClearSkies, accepted Heathrow was offering a concession on night flights but said it was disappointing it would not be extended to 6.00am.

He also questioned whether Heathrow was in a position to reduce air pollution.

"The bigger problem with air pollution is most of it comes from traffic and it's out of Heathrow's control to deal with air pollution from traffic. They can't really guarantee that air pollution levels can be brought down to EU legal limits," he added.

Image copyright Reuters

'Cleaner, quieter'

Mr Holland-Kaye said the airport was going beyond the recommendations of the Davies Commission and he was confident they could create a "cleaner, quieter Heathrow delivering more for the UK economy and that clears the way for the prime minister to make the right choice to expand Heathrow and deliver a stronger economy".

He said more investment in public transport and the use of electric and hybrid cars in the future would limit the impact from traffic pollution.

Mr Holland-Kaye blamed diesel vehicles for air pollution and said he was writing to the new London Mayor, Sadiq Khan, to request that he extended the ultra-low emission zone to the M25.

Mr Khan's manifesto stated that he would oppose a third runway at Heathrow and he favoured Gatwick as the more viable option.

The airport has pledged to create an ultra-low emissions zone for airport vehicles by 2025 and develop an emissions charging scheme for all vehicles accessing the airport.

But Mary Creagh, chair of the Commons Environmental Audit Committee, said Heathrow had to go "much further, much faster" in tackling air pollution.

"Promises on future rail links and air pollution charges are seven to 10 years away. People living near the airport need action on air quality much sooner and one quick win would be slashing fares on the Heathrow Express to encourage more people to use it."

Analysis by BBC transport correspondent Richard Westcott:

Heathrow's just played its ace.

The airport's gone further than many people expected in this latest bid to convince MPs, the government, and locals, that it should have a third runway.

In the past, Conservative Zac Goldsmith has said he'd resign as an MP if ministers went with Heathrow. Other cabinet members are known to oppose the scheme. It's not clear yet whether these concessions are enough to sway any of their opinions.

Then there's the locals, who always tell me that Heathrow has a habit of breaking promises.

Twenty years ago the airport vowed it would permanently rule out a third runway if only it could build terminal five.

That vow soon went out of the window.

Gatwick's bid

Stewart Wingate, chief executive of Gatwick Airport, described Wednesday's announcement by Heathrow's owners as a "desperate last throw from a project that has repeatedly failed".

He said Heathrow Airport's air quality plans failed "the most basic credibility test" and they could not promise traffic would not increase with a third runway.

"An expanded Heathrow will newly impact hundreds of thousands of people currently not affected by aircraft noise - an expanded Gatwick would impact less than 3% of this number," he added.

The Commons' Transport Select Committee published a report last week which urged ministers to set out a clear timetable for airport expansion.

Heathrow's plans:

The plan involves building a new 3,500m runway about two miles north of the two runways Heathrow already has at an estimated cost of £18.6bn.