Passengers using Heathrow will not face an increase in air fares despite the building of a third runway, the airport has announced.
The airport said it was confident it could keep landing fees - passed on to passengers in ticket prices - near existing rates despite expansion costs.
The industry should reduce costs and keep charges "close to current levels", the Department for Transport said.
Heathrow said it could now meet that challenge.
"Effectively we'll be able to expand the airport and passengers will continue paying what they pay today," a Heathrow spokesman said.
"It was key for the government that this gets done affordably, but also it's been a key issue for our airline partners as well."
Airport landing fees are the charges that airlines have to pay to use airports in the UK. Heathrow currently charges around £22 per passenger.
Heathrow's plans to build a new 3,500m runway about two miles north of the existing runways at an estimated cost of £17.6bn, to be operational by 2026.
Although specific plans will not be released until late 2017, the airport is proposing to delay some of the more expensive works.
An airport spokesman said: "It's not necessarily that these things won't be built.
"It's just that we can do some clever things to add additional capacity to our existing terminals up front.
"We can get more passengers in to help spread the cost."
Willie Walsh, the boss of British Airways' parent company IAG, warned expansion must be cheaper than the £17.6 billion budget estimated by the Airports Commission.
He feared landing fees could be raised and insisted airlines "are not going to pay for inefficient expansion".
Tim Alderslade, chief executive of Airlines UK, the industry body representing UK-registered carriers, said: "Heathrow is already the most expensive airport in the world and post-Brexit, the UK will need to compete even more with other hubs."
The airport said it has worked with carriers in a bid to develop an affordable strategy for building the third runway.