Air Seoul Inc., one of South Korea's six low-cost carriers, said Wednesday it has added two new routes this week as part of its initial expansion strategy.

Air Seoul, which started operations in October by offering flights to Takamatsu, began passenger services to Osaka and Guam on Tuesday, bringing the total number of routes it serves to 13, the company said in a statement. 

It plans to add two additional routes to Tokyo and Hong Kong on Oct. 31 and increase its fleet to five A321 jets by December from the current four, it said.

Air Seoul is a 46 percent-owned budget unit of Asiana Airlines Inc., the country's second-biggest carrier after Korean Air Lines Co.

Korean passenger carriers have diversified their routes to offset a sharp decline in travel demand from China amid ongoing political tensions between the two countries over the deployment of an advanced U.S. anti-missile system in South Korea to deter North Korean provocations.

In March, Beijing banned the sale of group travel packages to South Korea in retaliation against the deployment, which it argues is aimed at spying on its military. (Yonhap)