SEOUL - North Korea has completed preparations for a nuclear test and a possible window for carrying it out could be between Oct 16 and Nov 7, South Korean lawmakers briefed by its spy agency said on Wednesday.

Preparations for a possible nuclear test by North Korea, which would be the first since 2017, had been completed at the Punggye-ri test tunnel, where the reclusive state conducted six underground tests from 2006 onward, two legislators told reporters after a briefing by the National Intelligence Service (NIS).

The timing of the test could be determined by events like the party congress in China, North Korea's main ally, and the midterm elections in the United States, its chief rival, they said.

Also it would depend on whether Pyongyang can bring an outbreak of Covid-19 under control, they said.

"The NIS said they cannot calculate the probability but assumed that North Korea would make a comprehensive decision based on international relations and its Covid situation," said one legislator Youn Kun-young.

The other lawmaker Mr Yoo Sang-bum said the NIS sees North Korea's earlier claim of an end to Covid-19 as "unreliable" because it has repeatedly locked down and then reopened areas near the Chinese border where "mass vaccinations" are underway.

North Korean leader Kim Jong Un declared victory over Covid-19 and eased some restrictions last month, though the country has never confirmed how many people caught the virus, apparently lacking the means to conduct widespread testing.

Early this month, Mr Kim suggested that the isolated country could begin Covid-19 vaccinations in November, warning of a resurgence in outbreaks as levels of immunity formed from previous infections decline around October. REUTERS