Russian President Vladimir Putin is in China to discuss issues that include boosting energy cooperation and working to help resolve the Iranian nuclear standoff.
After Vladimir Putin met with Chinese President Hu Jintao, the two countries issued a statement saying they support investment in each other's energy sectors.
At a regular briefing, Foreign Ministry spokesman Qin Gang said energy cooperation, including the construction of new oil and gas pipelines, is high on the agenda.
Qin says energy is a very important area of bilateral cooperation for China. He said Russia has expressed, many times, that it wants to increase cooperation on the pipelines.
Later, Russian officials said a natural gas pipeline would be built to China in the coming years.
China has complained in the past that work on pipelines has moved too slowly. Russia is building a line through Siberia that would supply oil to both China and Japan.
China is Russia's top customer for oil and weapons. Trade between the two countries reached more than $29 billion last year and is growing. Some experts predict it may double during the next four years.
Mr. Putin's two-day visit also is expected to focus on efforts by Moscow and Beijing to resolve the Iranian nuclear standoff. On Monday, talks among Russia, China, the United States, Britain, France and Germany failed to reach an agreement on a U.N. Security Council statement on Iran's nuclear programs.
The U.S. and other countries fear Iran is trying to build nuclear weapons, in violation of the Non-Proliferation Treaty. China and Russia want the Security Council to proceed slowly in the matter.
Czeslaw Tubilewicz is a China studies professor at the University of Hong Kong who is following Putin's visit. He says Russia and China are using this issue to assert their commitment to what they describe as a "multi-polar" world.
"I think they are both sharing the same ideology that they both oppose the international community's efforts to interfere in other states internal affairs," he said. "On the basis of that, they would not like the United Nations to be too deeply involved in a crisis that, in their view, does not require the international community's involvement."
Russia has tried to prevent Security Council action against Tehran by proposing a plan for Iran to enrich uranium on Russian soil where it can be more closely monitored. China supported the plan, which Iran has rejected.
Analysts say Russian and Chinese leaders will use this visit to look for other ways to resolve the issue.