SEOUL, March 5 (Xinhua) -- The Democratic People's Republic of Korea (DPRK) on Thursday warned that it will not assure the safety of South Korean passenger planes flying over the territory east of its coastal line on the Sea of Japan, South Korea's Yonhap News Agency reported.

    According to Yonhap, the DPRK said that they "don't know what kind of military clashes may occur due to the joint war exercise (between South Korea and the U.S. military)."

    "We declare that we can no more assure the safety of South Korean passenger flights over our territory," Yonhap quoted a DPRK committee as saying.

    In response to the warning, South Korea's two major airline companies, the Korean Air and the Asiana Airlines, announced late Thursday that they have ordered planes using the Kamchatka route to change course as a safety measure.

    "All planes will be directed to fly further south over the Pacific Ocean when heading for or arriving from North America," a spokesperson for the Korean Air said late Thursday.

    The route is used to link Incheon International Airport on South Korea's west coast with U.S. cites like New York, Los Angeles and Chicago and some Russian destinations. Planes fly over the Kamchatka Peninsula and briefly use DPRK airspace over the Sea of Japan as a fuel-saving measure.

    Currently, 10 daily flights operated by the two South Korean flag carriers fly over the so-called flight information region administered by DPRK on average, local media said.

    The South Korean government has not made remarks over DPRK's warning.

    Local analysts said Pyongyang's warning was aimed to protest an upcoming joint military exercise between South Korea and the U.S. set for next Monday.

    The South Korean military said earlier last month that about 26,000 U.S. troops will participate in the drill while stressing that the exercise is "defense-oriented, focusing on military readiness posture."

    According to a news release by the U.S.-led United Nations Command (UNC), the U.S. aircraft carrier USS John C. Stennis and other navy ships of the 7th Fleet will join the drill set for March 9-20.

    The U.S.-led United Nations Command (UNC) announced early on the day that the DPRK and the UNC will hold general-level military talks on Friday over tensions on the Korean Peninsula. Thursday's warning by DPRK draws attention on the agenda and outcome of Friday's military talks.

    The inter-Korean relations have greatly deteriorated since South Korean President Lee Myung-bak, who adopted a hard-line policy towards DPRK, took office in February last year. The DPRK's military warned in mid-February that it was fully ready for "all-out confrontation" with South Korea.

    South Korean Defense Minister Lee Sang-hee said on Feb. 20 that the South Korean military will strike back if the DPRK attack them.