China has pledged to work with the Association of Southeast Asian Nations toward a code of conduct for the South China Sea on the basis of consensus, Foreign Minister Yang Jiechi said at the conclusion of his visit to Southeast Asia on Monday.

The five-day visit took in Indonesia and two of the four countries that have competing claims with China in the South China Sea - Malaysia and Brunei.

The visit came only weeks after an ASEAN ministerial meeting in Phnom Penh during which the Philippines inflamed tensions over the issue.

Yang's visit further emphasizes China's stance of cooperation and peaceful resolution on the South China Sea issue, and will soften tensions in the region, analysts said.

Solving disputes through direct talks between related parties is an important principle and is something that is agreed on by all signatories of the Declaration on the Conduct of Parties in the South China Sea, Yang told Xinhua News Agency.

Indonesia, Malaysia and Brunei all agreed on this principle during the visit, he said.

"China's sovereignty over Nansha Islands and their adjacent waters is based on solid and abundant historical and legal basis," said Yang. He said China's "opposition to the internalization and regionalization of the issues in the South China Sea is because it wishes to defend the consensus and the effectiveness of the DOC and maintain peace and stability in the region".

The difficult issue of the South China Sea requires countries in the region, ASEAN and China to work together closely, Indonesian Foreign Minister Marty Natalegawa said on Friday.

"I'm very much assured that our diplomacy is very much on track," Natalegawa said.

But recent actions by Manila and Hanoi have increased tensions in the region. Manila suggested the new code of conduct be a mechanism to solve territorial disputes, while Beijing believes it should be closer to the DOC signed in 2002 to deepen cooperation and reduce differences.

After the Phnom Penh meeting failed to produce a joint communique on the issue, diplomatic efforts made by Natalegawa eventually pushed the 10 ASEAN countries to release a six-point statement on the South China Sea in line with the DOC.

Malaysian Foreign Minister Datuk Seri Anifah Aman on Sunday urged Southeast Asian countries to settle their overlapping claims in the South China Sea before bringing them up with Beijing, saying both China and ASEAN are genuine in trying to find a peaceful solution to the dispute.

Yang's visit to the three countries will put pressure on Manila and Hanoi to begin to seriously address the DOC and return to talks with Beijing, said Gong Yingchun, an international law expert with China Foreign Affairs University.

"Curiously, the diplomatic blitz does not include stopovers in Hanoi and Manila, which Beijing has accused of challenging its sovereignty over the South China Sea islands," Manila Standard Today newspaper said on Friday.

"China doesn't skip the two countries on purpose or close the door of communication with them. On the contrary, China always remains open to direct talks with them to solve problems," said Zhang Jiuhuan, China's former ambassador to Thailand and Singapore.

"Some countries' provocations have resulted in risks to regional stability, and ASEAN countries would not take sides over the territorial issue but want closer strategic ties with China amid the global economic recession," he said.

A number of bilateral agreements on trade, infrastructure construction, education and culture were signed during Yang's visit.

In other territorial negotiations, China made a breakthrough in 28-year long bilateral boundary talks with Bhutan on Friday, the Foreign Ministry said on Sunday.

China would like to continue cooperation and negotiations with Bhutan to find a fair solution accepted by both sides, Vice-Minister of Foreign Affairs Fu Ying told the 20th round of boundary talks in Bhutan.

The two countries have not yet established diplomatic ties. The boundary talks are based on the Four Guiding Principles agreed to by both sides in the 1998 agreement to maintain peace and tranquility along the border.