SHANGHAI -- The relationship between China and the United States is not a "zero-sum" game, long-term cooperation is needed, said US Assistant Secretary of State Christopher Hill on Monday.

He told a press conference that since China and the United States have close economic links and share common interests in many areas, the two countries will rely on each other for a long period of time.

Calling it "one of the US's most important relationships", Hill said Sino-US relations should be carefully maintained and contacts promoted to find solutions for problems that arise.

Hill praised China for its progress in the protection of intellectual property rights, saying that China has taken effective measures to protect the 2008 Olympic Games trademark.

Hill reaffirmed the US's adherence to the one-China policy and the three Sino-US joint communiques.

Hill is his country's lead negotiator to the six-party talks, which aim to find a solution to the Korean peninsula nuclear issue.

He said China has contributed a lot to the resumption of the six-party talks, and the US will not pressure China to persuade the DPRK to come back to the talks. He voiced the hope that China would continue its active role in this regard.

Shanghai is the last leg of Hill's China tour. He will leave China late Monday.