Korean Air resumed full flight services on Tuesday after the government ordered at the weekend its unionized pilots to end a four day strike and return to work.

All cargo and passenger flights for both domestic and international destinations took off as expected, Korean Air said.

"As of today, all domestic and international flights are going according to schedule," said Korean Air spokeswoman Nancy Park.

Unionized pilots at the airline, which is also the world's biggest cargo carrier, returned to work on Monday after the government stepped in to end a strike over pay, citing concerns about damage to the economy, and mandated emergency mediation between Korean Air's management and its pilots.

Korean Air's Park said the walkout had cost the airline an estimated KRW67 billion won (USD$65.04 million).

The airline was forced to cancel about 60 percent of its scheduled flights over the period.

The Labor Ministry estimated on Sunday overall losses caused by the walkout, which began on Thursday, at KRW189.4 billion won, mostly resulting from lost income for transporting goods.

Korean Air accounts for 48 percent of the country's export and import cargo shipments and 41 percent of international passenger flights, according to the minister.

South Korea is heavily dependent on air cargo, sending most of its semiconductor and mobile phone exports by plane.

The government also intervened in August after pilots at the country's second-largest carrier, Asiana, had been on strike for almost a month.

The pilots' union at Korean Air is seeking a 3.5 percent rise in base salary, down from an initial demand for 6.5 percent. The management has offered a 2.5 percent increase in base pay.