(Adds comments on nuclear programme and quotes from Iranian president, paragraphs 6-9)
BEIJING, Sept 29 (Reuters) - China wants deeper trade ties with Iran, a senior Chinese leader was quoted as saying on Wednesday, praising relations between the two countries despite the controversy over Tehran's nuclear programme.
"China is willing to continue maintaining high-level contacts and exchanges at all levels with Iran and deepen mutual political trust," the People's Daily quoted Li Changchun, Communist Party chief propaganda official, as saying.
The two sides should "deepen trade and economic relations, earnestly put into effect signed agreements and contracts, develop infrastructure, communication, auto and light rail cooperation", Li said during a visit to Iran.
China and Iran should also encourage and lead exchanges between their respective companies, he added.
"The positive and stable development of ties has brought real benefits to the two peoples," Li told Iranian officials.
Li later told President Mahmoud Ahmadinejad that China wanted to resolve the stand-off over Iran's nuclear programme through talks, in a repetition of China's standard line.
"China is willing to continue playing a constructive role in this regard," Li said, according to the Xinhua news agency.
Ahmadinejad expressed "appreciation for China's longstanding efforts to help solve the Iranian nuclear issue", adding that "Iran is committed to solving the issue through negotiations", Xinhua said.
"Iran will continue implementing friendly policies towards China," the president was quoted as saying.
China has backed U.N. Security Council resolutions pressing Iran to abandon disputed nuclear activities, which Western governments say are aimed at giving Iran the means to make nuclear weapons. Iran says the programme is purely for peaceful purposes
Western governments have pressed China to loosen its energy and economic ties with Iran, which they see as shielding Iran from international pressure.
China has pushed back at U.S. pressure on its business and oil trade with Iran in comments published last month, saying Chinese trade dealings with Iran should not be criticised.
Iran is a major supplier of crude oil to China, the world's second-biggest consumer of oil after the United States.
The United States has urged China to tap other suppliers, but China has condemned unilateral U.S. and E.U. sanctions aimed at Iran's energy sector. (Reporting by Ben Blanchard; Editing by Ken Wills)