Riot police in Calgary were standing by for another major protest at a meeting of the world's oil industry leaders Monday, even though there was no trouble when about 1,000 marched downtown Sunday.

Demonstrators are using the World Petroleum Congress to protest against the oil industry's record on environmental and human rights issues. Many activists also believe the industry is responsible for global warming.

On Sunday, police, who came from four provinces, escorted the crowd for one kilometre as demonstrators carried signs that read, "No blood for oil" and "People, not profit."

A few protesters, dressed in dinosaur outfits, rode bicycles bearing slogans such as "Extinction stinks."

Critics say such a heavy police presence wasn't necessary. Dozens of officers watched the march, carrying pepper spray and stun guns in case of any confrontations.

The city wants to avoid violent clashes such as the ones in Seattle during meetings of the World Trade Organization last year.

The demonstration was held at the start of the five-day congress to protest against the oil industry's record on environmental and human rights issues. Some 3,000 delegates from 90 countries are in Calgary.

Premier Ralph Klein asked protesters to respect the rights of those attending the meetings.

"The protest is the essence of democracy. Everyone has a right to free speech, and citizens of this city and this province also have a right to move freely and not be impeded," he said.

"Protest peacefully . . . but don't get in the way of people doing their day to day business."

Prime Minister Chretien opened the meeting by urging delegates and the oil industry to adapt to climate change. He also highlighted environmental progress made by Canada, using oilpatch operations in Alberta, Saskatchewan, the North and Newfoundland as examples.