In this photo released by North Korea's official Korean Central News Agency, Aug. 31, a worker disinfects a school in North Korea. Yonhap

North Korea said Monday it has strengthened preventive measures against COVID-19 in response to growing concern about the Omicron variant, a move that heralds a further delay in easing its stringent border control.

The reclusive nation had been seen preparing to reopen its land border with China and Russia, at least partially, before the end of this year.

But the emergence of a new variant of the coronavirus has put the country and many other parts of the world on high alert.

In a report, the state-run Korean Central News Agency (KCNA) pointed out the variant, which is five times more contagious than the delta one, is causing serious worries around the globe.

The country's officials and other "workers" are concentrating all efforts on "thoroughly ensuring perfection" in the emergency virus control and prevention campaign, it added. The KCNA piece marked the latest in a string of Omicron-related reports by the country's tightly-controlled media outlets since Saturday.

In a bid to stave off the spread of COVID-19, North Korea has implemented strict virus curbs, including border lockdowns that have halted cross-border rail services, since the start of last year.

The North has claimed to be coronavirus-free and reported no confirmed case to the WHO so far. (Yonhap)