Vietnam and China said on Wednesday they had finished demarcating their land border, a diplomatic milestone for the Communist neighbours who fought a brief but brutal war along the frontier 30 years ago.
Vietnamese and Chinese leaders had set a deadline to complete the task by the end of 2008, and negotiators announced with less than six hours to go that the goal had been achieved, underscoring the sensitivity of the territorial dispute between the two countries with a chequered past.
"The completion of the land border demarcation between China and Vietnam will promote the development of the China-Vietnam strategic partnership," Chinese Deputy Foreign Minister Wu Dawei said.
"The completion of this work will also benefit peace, stability and development in this region."
A more thorny maritime territorial dispute was not mentioned by the negotiators or in a joint statement on Wednesday.
The two sides agreed to work closely together and co-perate to protect peace and stability in the border area.
China supported the Vietnamese Communists in their decades-long war against the French colonial government and U.S.-supported South Vietnam.
But Vietnam, traditionally wary of its larger Asian neighbour, eventually gravitated into the sphere of influence of the Soviet Union.
In early 1979, China and Vietnam fought a brief border war after Vietnamese troops overthrew Cambodia's genocidal Khmer Rouge that favoured Beijing.
China and Vietnam both claim sovereignty over the Paracel archipelago and the Spratly Islands, a string of rocky outcrops in the South China Sea suspected of containing large oil and gas deposits and also claimed by Taiwan, Brunei, Malaysia and the Philippines.
In 1988, the two fought a brief naval battle near one of the Spratly reefs in which more than 70 Vietnamese sailors died.
While the two have become major trade partners since normalizing relations in 1991, taking steps to ease tensions, the maritime conflict remains sensitive.
In July, China pressured Exxon Mobil Corp to pull out of an oil exploration deal with Vietnam that it saw as a breach of Chinese sovereignty. In May, BP halted plans to conduct exploration work off the southern Vietnamese coast citing territorial tensions.
Earlier on Wednesday, the Chinese news agency Xinhua said China would soon complete a third mission to clear its border with Vietnam of land mines. China had cleared more than 6,800 land mines at its Friendship Pass border area with Vietnam, it reported, citing the headquarters of the regional army command.
"No one really knows how many mines are buried on the border," Lieutenant-Colonel Fu Xiutang, one of the leaders of the mine-clearing mission was quoted as saying. The number has been estimated to be as high as two million.
Almost 6,000 Chinese in Wenshan Prefecture along the border have died or were injured by land mines since 1979, Xinhua said, citing the Yunnan local government.