SUDBURY, Ont. - Liberal Leader Michael Ignatieff is cancelling a week-long trip to China due to his self-declared threat of a fall federal election, The Canadian Press has learned.

Ignatieff was to leave Friday for what he'd billed as an "imperative" international trip to Beijing and Shanghai to rebuild diplomatic relations with the Asian economic giant.

But Liberal insiders say he spoke Friday morning with Canada's ambassador to China, David Mulroney, who had been helping co-ordinate the trip, and postponed it for the time being. Ignatieff plans to reschedule the visit as soon possible, said a party source.

The Liberal leader has been sharply critical of the Harper government for what he called "bungling" the China file, but his own sudden cancellation may well be viewed as another snub.

Just last month, Ignatieff announced that his Liberal delegation would travel to China with the goal of "salvaging this important historical partnership right away."

The Liberals, in an effort to put the best face on their change of plans, say Ignatieff stressed to Mulroney the importance of engagement with China and the need to have China at the table at the G20 steering committee.

Prime Minister Stephen Harper has not visited China during his three-plus years in power, but plans to do so later this autumn -- barring an election.

That trip would mark a dramatic and speedy thaw in relations.

The prime minister declined an invitation to the opening ceremonies of last year's Olympic Games in Beijing, and raised diplomatic hackles in 2007 when he met the Dalai Lama, whom Beijing considers a Tibetan separatist threat.

Tibet's spiritual leader had been named an honorary Canadian citizen.

Canada also aggressively protested the imprisonment of Chinese-Canadian Huseyin Celil and Harper used strong language in referring to his concern over human rights in China.

"I don't think Canadians want us to sell out important Canadian values," Harper said in 2006 after a potential meeting with Chinese President Hu Jintao suddenly fell through.

"They don't want us to sell out to the almighty dollar."

But in recent months, four senior Conservative cabinet ministers have visited China, including Finance Minister Jim Flaherty, Foreign Affairs Minister Lawrence Cannon and International Trade Minister Stockwell Day.

All have stressed economic relations with China, an apparent return to the previous Liberal government strategy of "constructive engagement."