The head of Vietnam's ruling Communist Party, Nong Duc Manh, arrived in China on Friday for talks with his Chinese counterpart Hu Jintao and other leaders, reported dpa.
The official Xinhua news agency said Manh was also scheduled to meet Wu Bangguo, the official number two in China's Communist Party, and Premier Wen Jiabao, who ranks number three in the party, during a previously unannounced four-day visit.
Meetings between leaders of communist neighbours China and Vietnam are normally presented as party-to-party rather than state-to-state.
"The visit is aimed at creating a new driving force for continuous development of Vietnam-China relations," the agency quoted Vietnamese Deputy Prime Minister Pham Gia Khiem, who travelled to China with Manh, as saying earlier.
Manh handed Chinese officials in Beijing a list of relief materials for survivors of the recent earthquake in the south-western province of Sichuan, the agency said.
The two batches Vietnamese relief materials weighed a total of about 15 tons and included 150 tents and 10,000 boxes of milk powder, the agency said.
China and Vietnam fought a brief but violent border war in 1979.
Armed skirmishes have broken out between them as recently as 1988, when they fought a brief naval battle over the disputed Spratly Islands in the South China Sea.
But economic and diplomatic ties have gradually improved over the last decade.
"In the new era, the relations between China and Vietnam develop unceasingly with frequent visits of top leaders of the two countries," the Xinhua report said.