Finnair is raising capacity between Heathrow and Helsinki next summer to cope with an expected rise in demand.
Four flights a day are scheduled with wide-body Airbus A350 and A330 aircraft deployed on two of the four services.
The 2022 schedule compares with around three flights a day currently by smaller narrow-body aircraft.
The carrier is preparing for an expected gradual post-pandemic opening of Asia.
The airline plans to serve more than 100 destinations from its Helsinki hub including new long-haul services to the Far East for summer 2022.
New routes include Busan in South Korea and Dallas in the US.
Finnair’s focus on Japan, which is dependent on the lifting of travel restrictions, will see services resume to all five destinations – Tokyo, Osaka, Nagoya, Fukuoka and Sapporo – and a sixth new route to Tokyo’s Haneda airport.
Helsinki airport is also expanding with new arrival and departure halls opening next month followed by a new security control and check-in area in May 2022.
Finnair plans up to 40 flights a week between Helsinki and Japan from March 27, 2022.
Daily flights to Tokyo Narita and Haneda airports will provide a total of 14 weekly frequencies to the Japanese capital.
Finnair will also fly daily to Nagoya and Osaka and will introduce double dailies to Osaka in June.
The airline’s Sapporo service will be introduced for the summer season for the first time with two weekly flights, and Fukuoka in southern Japan served with three flights a week.
Daily flights are scheduled to Hong Kong, Seoul, Singapore and Bangkok, and twice a week to Shanghai, subject to regulatory approval.
Daily services to Delhi start in June and the new Busan route in South Korea will be launched in May with flights three times a week.
Chief commercial officer Ole Orver said: “We look forward to the world opening again. Before the pandemic, Japan was our single largest market outside our home market Finland, and we look forward to returning to all our five destinations in Japan.
“We are also opening a new route to Busan in South Korea, demonstrating our continuous commitment to offering the best connections between Europe and Asia via our Helsinki hub.
“In addition, are pleased to strengthen our network in the US by adding Dallas as a new destination. Our customers will be able to enjoy great connections to other cities in North America through the extensive network of our alliance partner, American Airlines.”