He was speaking as part of celebrations marking 200 days to go until the Opening Ceremony of the first South Korean Winter Games.

Officials are desperate to ensure Northern participation as a means to show the unifying power of sport at a time when relations are increasingly tense politically.

"We don't need to hurriedly expect or be pessimistic about [the North Korean participation]," Moon was quoted as saying by the Yonhap press agency.

"And, we will leave the door open until the very last minute.

"The International Olympic Committee (IOC), too, has opened the doors for North Korea's participation and now all that is left is North Korea's decision."

Relations are at an increasingly delicate point following the launch earlier this month by North Korea of an intercontinental ballistic missile capable of carrying a nuclear warhead.

Moon has advocated increased dialogue with their reclusive neighbour since assuming the Presidency in May.

It has even been suggested that a unified North and South Korean team could participate in Pyeongchang.

This proposal has been dismissed as unrealistic, however, by figures including North Korean IOC member Chang Ung.

North and South Korea symbolically marched together at the Opening Ceremonies of Sydney 2000 and Athens 2004 but competed separately.

North Korea boycotted Seoul 1988 in the South's capital. 

They have, though, participated at other more recent events held on South Korean soil, including at the 2014 Asian Games in Incheon. 

North Korea's only realistic remaining chance of qualification for Pyeongchang 2018 is the pairs figure skating through Ryom Tae-ok and Kim Ju-sik.

The Asian Winter Games bronze medal winners narrowly missed out on securing a place earlier this year but have another chance in September. 

It is possible that others could be granted wildcard places through the Tripartite Commission system.

Moon met with Organising Committee staff and volunteers as well as Olympic and Paralympic ambassadors during a visit to the main snow venue cluster at Alpensia.

He promised that Seoul will play a greater role in the final six months of preparations.

"For the Government, this will be the first major international event since we took office," he said.

"I believe the Government has an obligation to make the Games a success.

"Up until now, the Government left this job to the Organising Committee and Gangwon Province. 

"Now with 200 days left, the Central Government will join forces to make the Pyeongchang Olympic Winter Games a complete success.

"This is a chance for the people of our nation to heal and regain hope by successfully hosting the Olympic Winter Games."

A special theme song, entitled Let Everyone Shine, was premiered at the G-200 Fireworks Festival in Chuncheon in nearby Gangwon Province over the weekend.

R&B singer Insooni, a Pyeongchang 2018 honorary ambassador, performed the song live in front of an excited crowd of thousands. 

“I am honoured to sing this very special song at the 200 days to go celebration and to be an ambassador for the Olympic and Paralympic Winter Games Pyeongchang 2018," she said.

"Music has the power to connect people together, just like sport does. 

"This is a special moment where the two have come together and we can all celebrate this exciting time for Korea and look forward to an amazing event in 200 days’ time."

The Winter Olympics will run between February 9 and 25.