Canada's Prime Minister Stephen Harper blundered by not attending the Olympic Games opening ceremony in Beijing, his predecessor said Monday, lamenting a relapse in ties with China.

"You know, they have a collective memory there that is very important," said ex-prime minister Jean Chretien in a speech to the Canadian Bar Association.

"It is the second-biggest economy in the world. In 50 years it will be the biggest economy in the world. Starting with (former prime ministers) Diefenbaker, and then with Trudeau, and all of us, we established very good relations with China," he later told reporters in Quebec City.

"And suddenly, you break a bridge. It would have been easy just to be there," he said, quoted by local media.

Harper skipped the August 8 opening ceremony, citing a scheduling conflict. During his term, he has repeatedly criticized China for its human rights record.

In his address to the lawyers, Chretien, who led four trade missions to China as prime minister (1993-2003), said bestowing honorary Canadian citizenship to the Tibetan spiritual leader the Dalai Lama last year has hurt bilateral trade too.

"We are (now) at the bottom of the ladder in terms of having any influence with China," he said. "Ask any businessman who has been to China (of late), and he will tell you the same thing."