South Korean President Park Geun-hye has praised the deployment of South Korea’s FA-50 aircrafts on Thursday, while ordering the country’s military to remain at full readiness, Yonhap News Agency reported.

“Now, our security situation is very grave”, Park said in a ceremony, marking the deployment of the fighter jets, as quoted by Yonhap News.

Park’s words came amid new tensions between the two Koreas. Just yesterday, North Korea rejected Seoul’s offer to hold high-level talks, the source said.

Park said the deployment of the FA-50 aircrafts marked “a historic day”. South Korea deployed 20 fighter jets last month and there are plans to deploy another 40 new planes in future, Yonhap News reported.

The FA-50 is a new version of light combat aircraft manufactured by Korea Aerospace Industries (KAI). The development of the FA-50 began back in 1997 and since then six new prototypes have been built. The planes have an advanced radar system equipped witha night vision imaging system. The FA-50s are armed with 20mm cannon and air-to-air missiles, according to the Airforce Technology website.