Officials from the construction ministry said at a meeting with the central province of Quang Binh on Wednesday that the ecology and all the heritage values of the national park will remain undisturbed for the next 15 years.
The more than 344,000-hectare (850,000-acre) park won UNESCO recognition as a heritage site in 2003 thanks to its 300 caves and grottoes, which date back some 400 million years.
Members of the British Cave Research Association explored the caves several years ago with help from local man Ho Khanh.
Son Doong, one of the caves, has been named the world’s largest.
Images of Son Doong and other caves last month appeared on the US popular talk show Good Morning America. ABC’s Ginger Zee compared the scenes to “Avatar.”
Nguyen Huu Hoai, mayor of the province, said it has opened some caves including the five-kilometer Son Doong to tourists and will continue to keep the operation small.
Hoai said it will not build roads or shelters in the caves, to keep it a “real treasure.”
The province expects to draw 1.35 million tourist arrivals to the caves by 2030, including around 55,000 foreigners.
It received widespread opposition last October when it announced plans to allow a company to build a 11-kilometer cable car system at Son Doong to allow tourists to admire the landscape from above.
Experts and tourists voiced their environmental concerns, which then prompted the government to ask the province to cancel the project.