"(The military) is trailing (North Korea's possible missile launch) as the launch is seen ready," Defence Minister Kim Kwan-jin told lawmakers at a parliamentary defence committee.
North Korea's "military parade is estimated" to be held around April 15, reports Xinhua.
His comments came amid rising expectations from North Korea to launch missiles around April 15 when Pyongyang celebrates the birthday of Kim Il-sung, North Korea's founder and the late grandfather of the current leader Kim Jung-un.
Pyongyang was believed to have moved intermediate-range missiles, believed to be Musudan, to its east coast. Other missiles, including Scud and Nodong, were also believed to be mounted on mobile launchers known as the transporter-erector-launcher (TEL).
The Musudan is estimated to have a range of about 3,500 km and can reach the US military base in Guam. The Scud is estimated to have a range of between 300 and 500 km, with the range for Nodong estimated at 1,300-1,500 km.
Kim said there have been no signs of North Korea waging a full-scale war, but he noted that the military is preparing for the local provocation that could happen "at any time".