BEIJING - China and Vietnam on Tuesday agreed not to let maritime problems affect relations, as the neighbors have been recently involved in a maritime dispute.

The two countries also signed an agreement of basic principles, which they consider "highly important to the proper settlement of the maritime dispute".

The agreement was reached as General Secretary of the Communist Party of Vietnam Central Committee Nguyen Phu Trong arrived in Beijing on Tuesday and met Hu Jintao, general secretary of the Communist Party of China (CPC) Central Committee and Chinese president.

Welcoming Trong, who is on his first visit here since becoming head of the ruling party of Vietnam, Hu said the leaders of both countries should maintain dialogue on the maritime problem.

"No action should be taken to complicate or exacerbate the maritime dispute before a final solution is reached," Hu said. "Instead, the two sides should settle the problem in a cool-headed and constructive way."

Hu also urged Vietnam to consider joint development of disputed areas of the South China Sea, and to "take concrete steps as soon as possible".

In response, Trong said if the maritime problem is not properly managed it will affect the broad picture of bilateral relations.

"The Vietnam side is willing to maintain direct communication with the Chinese leaders on a proper settlement of the maritime dispute," Trong said.

He also said Vietnam is willing to implement the principle agreement on settling the maritime dispute reached on Tuesday, and to continue dialogue and negotiation.

The two leaders pledged "not to let the maritime problem affect ties between the two countries, two peoples and the peace and stability of the maritime region".

The guidance agreement, long awaited by both countries, was one of five agreements signed on Tuesday. The others involved agreements on boosting party-to-party cooperation, economic cooperation, education and transport. Details of these agreements were not released.

Covering an area of more than 3.5 million square kilometers, the South China Sea is believed to hold vast deposits of oil and natural gas.

China, Vietnam, the Philippines, Brunei and Malaysia all lay claim to some islands and reefs in the area, with some countries having begun development of maritime resources in disputed regions.

To solve disputes, in 2002 China and the Association of the Southeast Asian Nations signed the Declaration on the Conduct of Parties in the South China Sea, in which they pledged to jointly safeguard regional stability, cooperate in the area and resolve disputes through peaceful talks between claimants.

However, tension has lingered as some countries have continued their maritime development in disputed areas. In a recent case, Vietnamese companies had been reportedly seeking partnerships with foreign countries to tap gas resources in the disputed maritime region.

The guidance agreement signed on Tuesday is the first of its kind signed directly between China and the other claimants, with all sides giving it high praise. Yet it remains to be seen whether a maritime law to be introduced by the Vietnamese legislature later this year will also carry the spirit of cooperation written into Tuesday's agreement.

China and other claimants have held negotiations in recent years to reach similar agreements.

Despite recent tension, Vietnamese media has paid close attention to Trong's visit. The national English-language daily, Vietnam News, said "the key objective of the visit is to promote the Vietnam-China strategic and comprehensive partnership".

The newspaper said the many agreements concluded between the two countries in the past have become solid foundations for long-term cooperation.

Vietnam Investment Review carried an article on Monday saying that Trong's visit will "provide a cemented platform for accelerated trade and investment between the two comprehensive strategic partners".

The article said Trong's visit is "expected to bring the bilateral relationship to a new height", with measures to strengthen bilateral ties by placing trade and investment high on the agenda.

Nhan Dan, the party and state flagship newspaper, said in an editorial on Tuesday that strengthening relations with China is in line with the country's diplomatic priorities, and that Trong will discuss China's experience of economic growth during his visit.

China has been Vietnam's leading trade partner since 2004, with two-way trade exceeding $27 billion in 2010 and reaching $15.7 billion in the first half of this year.

Trong said the ruling Communist Party of Vietnam and the government view developing ties with China as a diplomatic priority.

"Vietnam will unwaveringly ... promote high-level visits, enhance political mutual trust and strengthen cooperation in all sectors," Trong said. He pledged to promote "comrade plus brotherly" bilateral ties.

The five-day tour will also bring Trong and his high-ranking delegation to visit some of China's economic hubs to see firsthand the latter's rapid economic growth.

Trong is expected to visit the high-tech hub of Zhongguancun in Beijing on Wednesday morning before meeting Chinese Premier Wen Jiabao in the afternoon.