Cultural authorities in South China's Guangdong Province said yesterday that none of the relics recovered from the wreck of the ancient Nanhai I had been put up for sale overseas.

Jing Lihu, deputy director of the Guangdong provincial cultural department, said: "All of the relics salvaged from the ship belong to the national treasure and no one has the right to do so (sell them)."

The Nanhai I, which was a serendipitous find in 1987 in the seas around Yangjiang in Guangdong, is the largest cargo ship of the Southern Song Dynasty (1127-1279) so far discovered on the ancient "Marine Silk Road" of the South China Sea.

A host of green-glazed porcelain plates, tin pots, shadow-blue china and other rare items were found during an initial exploration of the ship.

Archaeologists have said there could be 60,000-80,000 relics on the ship, which some cultural experts have estimated to be worth about $100 billion.

"We have established a sound management system for protecting the relics salvaged from the ship. And so far we have no record of any public sales," Jing said in an interview with China Daily yesterday.

Recent reports by some Chinese media claimed that a relic from the Nanhai I had been put up for auction in Europe with a reserve price of about $1 million.

"That was a false report, which did not give any information about when or where the auction took place," Jing said.

Huang Daoqing, director of the Guangdong provincial archaeology research institute, said: "National treasures are not allowed to be put up for public sale, and so far all of the relics recovered from the ship have been properly protected."

He added that it was hard to estimate the total value of the antiquities, as "many have yet to be recovered".

Salvage work on the wreckage site was able to resume yesterday thanks to improved weather conditions in the seas off Yangjiang, sources with the Guangzhou salvage bureau under the Ministry of Communications, said.

A massive "steel box" to be used to help lift the ancient ship was put into place last Thursday, but bad weather led to work being suspended.

Wang Wenyi, an official in charge of the salvage operation, said: "The ancient ship (once it is has been recovered) will be put in a huge glass pool, in which the water temperature, pressure and other environmental conditions will replicate the sea in which it has spent the past 800 years."

He said the salvage operation was expected to be completed before July, weather permitting.