China said it was not the proper time to arrange meetings between Chinese Premier Wen Jiabao and the Japanese side at the UN conferences in New York, Foreign Ministry spokeswoman Jiang Yu said at a regular news briefing on Tuesday.

Premier Wen left Beijing Tuesday afternoon for a series of United Nations conferences.

Wen's UN trip, slated from Sept. 21 to 23, includes a UN high-level meeting on the Millennium Development Goals (MDG) and the general debate of the 65th session of the UN General Assembly.

Wen would also attend a meeting of leaders from the UN Security Council member states, a discussion panel on the MDG and HIV/AIDS, and meet with UN Secretary-General Ban Ki-moon, Assistant Foreign Minister Liu Zhenmin said last week.

Wen would deliver speeches at the UN conferences to elaborate China's stance and measures on development, the world situation and the prevention and treatment of HIV/AIDS, Liu said.

The premier would also meet with U.S. President Barack Obama during his trip, Liu said. The meeting is expected to be an important chance for China and the United States to further bilateral ties and deepen mutual trust as top leaders from the two countries talk face to face.

Earlier this month, U.S. National Economic Council Chairman Larry Summers and Deputy National Security Adviser Thomas Donilon visited China and held meetings with several Chinese leaders.

Wen is making the trip as guest of UN Secretary-General Ban Ki-moon.