Korean Air Lines Co. said Wednesday it has begun to use two converted planes to transport cargo on routes to the United States in the latest move to offset a sharp decline in air travel demand amid the coronavirus pandemic.

The biggest carrier in South Korea has recently converted two B777-300ER jets into cargo planes after obtaining approval from the transport ministry.

"One of the two converted aircraft flew to the Rickenbacker International Airport in Ohio on Tuesday, and the other is scheduled to fly to the same airport on Thursday," a company spokesman said.

The move is in line with global airlines, which are now using their passenger planes for cargo flights, either by using cargo seat bags or removing seats.

In June, Korean Air began to carry cargo in cargo seat bags, which attach to the seats of passenger jets, as the pandemic drove down travel demand and its earnings.

Cargo-carrying demand has jumped this year as more than 180 countries and territories closed their borders or imposed entry restrictions on incoming passengers amid virus fears.

Increased cargo demand helped airlines offset a sharp decline in air travel demand in the April-June quarter.

On a parent basis, Korean Air shifted to a net profit of 162.4 billion won ($137 million) in the second quarter from a net loss of 80.78 billion won a year earlier as it focused on obtaining more cargo-carrying orders.

Korean Air said it may consider making another request to the ministry to convert additional passenger jets into cargo planes if cargo demand continues to rise amid the COVID-19 pandemic.

The government will review the request if there is an additional request from the national flag carrier for plane conversion, a ministry official said, adding safety should be guaranteed by manufacturer Boeing for the conversion.

Korean Air has a fleet of 143 passenger jets, including 26 B777-300ERs, and 23 cargo planes.

The carrier expects its overall cargo volumes will increase by at least 10 tons to 34 tons after the conversion.

Korean Air's low-cost affiliate Jin Air Co. also plans to convert a B777-200ER jet into a cargo plane next month after obtaining government approval.

Asiana Airlines Inc., the country's second-biggest carrier, said it is considering the plane conversion plan as the pandemic shows no signs of slowing down. (Yonhap)