South Korea will remove a concrete structure at the runway of one of its southern airports, the scene of a plane crash that killed all but two of the 181 people on board last month.

South Korea's transport ministry said on Wednesday that it would remove the concrete embankment installed at Muan International Airport following last month's Jeju Air crash, its deadliest domestic air disaster.

Airlines have been increasingly outsourcing repair and upkeep work to other countries, but experts and consumer groups disagree about its impact on safety.

Seven airports will also have their runway safety areas adapted following a review of all South Korea's airports that was carried out after the crash - the deadliest in the country's history. The Jeju Air flight was bringing passengers home from Thailand after Christmas when it made an emergency landing at Muan airport and exploded after slamming into a concrete barrier at the end of the runway.