Seoul, Jan 24 (IANS): South Korea's Unification Ministry said on Monday that it is closely monitoring North Korea's nuclear and missile activities after Pyongyang hinted last week at lifting its self-imposed moratorium on nuclear and long-range missile tests.

On January 19, North Korea held a politburo meeting of its ruling Workers' Party, presided over by leader Kim Jong-un, and decided to consider restarting "all temporally-suspended" activities, citing Washington's "hostile policy" against the country, reports Yonhap News Agency.

Asked about a news report that said the North appears to be maintaining its Punggye-ri nuclear test site, which it is said to have dismantled in 2018, Ministry spokesperson Lee Jong-joo declined to confirm "detailed intelligence matters on North Korea's nuclear facilities" but said the government is monitoring related moves.

"The government is following North Korea's nuclear and missile activities under close South Korea-US coordination," Lee told reporters here.

It is also monitoring the possibility of a notable event in North Korea to mark key national holidays -- the 80th birthday of Kim Jong-un's late father, Kim Jong-il, on February 16 and the 110th birthday of his late grandfather, Kim Il-sung, on April 15 -- amid signs the country may be preparing a military parade.

Pyongyang tends to commemorate every fifth and 10th anniversary with major events.

Tensions have ratcheted up on the Korean Peninsula in recent weeks after the North conducted four missile tests, including two of what it claims to be a hypersonic missile, since the start of the year.