Ryanair chief executive Michael O'Leary said Britain should focus on adding capacity at airports other than London's Heathrow and lowering passenger taxes as he laid out plans to deploy an extra 100 aircraft in the UK in the next eight years.
British finance minister Rachel Reeves has just given the government's backing to a long-delayed new runway at Heathrow Airport as part of her plan to revitalise the country's sluggish economy.
O'Leary said on Wednesday he did not expect Heathrow's third runway to be built any time soon.
"You could grow today in Manchester or Birmingham. You could grow at Stansted," O'Leary told reporters in London.
"I don't personally think a third runway in Heathrow is likely. I suspect a second runway in Gatwick is more deliverable," he told reporters.
Ryanair is due to receive 300 new aircraft in the next eight years, and a third of those will go into Britain, which accounts for about 40% of its business.
The company plans major investment in other British airports along with the 100 aircraft.
O'Leary said the British government should focus on developing other airports in places like Bournemouth or Edinburgh and lowering passenger taxes if it wants to boost economic growth.
Meanwhile, Ryanair is confident that Boeing will ramp up its production of 737 MAX jets to 38 per month this summer and will be allowed by US President Donald Trump's administration to then increase that to 42, the airline's CEO said on Wednesday.
Michael O'Leary, whose airline is one of the largest customers of the 737 MAX, was speaking after meetings with Boeing management in Seattle earlier this month.
He said Ryanair expects to take delivery of the last 29 of its current 737 MAX order between August and November this year. In quarterly results on Monday he said they would be delivered before the end of March.
"Those deliveries are ... dependent on Boeing getting monthly production up to 38 by the end of this summer, and then getting permission from the FAA to go up to 42," O'Leary told a news conference in London, referring to the US Federal Aviation Administration.
"I'm pretty confident under the Trump administration, they will be much more pro-American manufacturing and American jobs... much more supportive of Boeing's recovery," he said.
"I don't think the Biden administration was particularly helpful to Boeing."
Boeing CEO Kelly Ortberg is due to visit Ryanair in Dublin for further meetings in February, O'Leary said.
"I would be very optimistic that Boeing's turnaround will continue and will accelerate," he said.
