Delta Air Lines and Vietnam Airlines expanded their codeshare agreement, adding Delta codes on all Vietnam Airlines flights between Tokyo (HND) and Hanoi (HAN).

Codeshares are agreements between airlines enabling passengers to book flights with different operating airlines under a single itinerary. Travelers collect a single boarding pass at their departure, and luggage is checked through to the final destination.

With this new agreement, passengers on Delta’s flights from Minneapolis (MSP) and Los Angeles (LAX) to Tokyo (HND) can connect on Vietnam Airlines’ flights (HND)–(HAN).

Delta is transferring all of its U.S.-Tokyo flights from Narita (NRT) to Haneda this month. Delta said once this process is complete, all Delta customers flying from Atlanta (ATL), Detroit (DTW), Seattle (SEA), Portland (PDX) and Honolulu (HNL), in addition to Los Angeles and Minneapolis, can connect to Vietnam Airlines’ Hanoi flights at Haneda.

Vietnam Airlines’ code will also appear on all Delta flights in and out of Haneda airport.

“This is going to be a transformative year for Delta in Japan as we consolidate our services in Haneda next month,” said Perry Cantarutti, senior vice president-alliances, Delta Air Lines.

“The partnership with fellow Skyteam member Vietnam Airlines, further strengthens Delta’s position in Haneda as the largest U.S. airline, while enhancing connectivity between the two countries.”