QUEBEC, Canada (BBC) -- Talks between the U.S., Mexico and Canada are under way in Quebec as they aim to discuss trade and security.

Plans to modernize the North American Free-Trade Agreement (NAFTA) are on the agenda as well as market volatility.
More than 2,000 people turned up to protest on Monday, with critics fearing that a stronger NAFTA would come at the cost of national sovereignty.
But high levels of security and police in riot gear has prevented protestors from disrupting the event's first day.
In the United States opponents have argued that NAFTA has undermined manufacturing jobs, despite generating $700b in trilateral trade.
Police have blocked demonstrations within 15 miles of the summit complex.
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U.S. President George W. Bush, Mexico's President Felipe Calderon and Canada's Prime Minister Stephen Harper met in Montebello, a 90-minute drive from Ottawa.
But President Calderon later said that he would leave on Tuesday after the trilateral meeting with his U.S. and Canadian counterparts.
""I have decided to suspend my official visit to Canada and personally head the tasks for the protection of the population in case of disasters,"" said Calderon.
Earlier, demonstrators had marched to the Canadian Parliament on Sunday in protest against the Iraq war, globalization and the escalating battle for control of the resource-rich Arctic region.
""The whole world is rejecting this notion of unlimited growth,"" she said. Efforts to update NAFTA, a central plank of a broad-ranging Security and Prosperity Partnership agreed by the trio in 2005, will be central to the talks.
Critics of NAFTA and other free trade deals argue that they have destroyed jobs in poorer countries and damaged the environment.
Trade between the three partners has increased by more than 10% a year since the agreement, which paved the way for tariffs to be cut on key products, was ratified in 1994.
----------Protectionist pressures
Growing protectionist sentiment in Washington has meant NAFTA and other Free-trade agreements have come under growing scrutiny.
Leading Democrat Presidential candidates have all attacked the agreement as unfair because U.S. labor laws more strictly enforced than those of its trading partners. There is also unease about NAFTA in Mexico with farmers opposed to the imminent liberalization of the maize industry to corn imports from the U.S.
Other issues on the agenda include co-operation over security and energy issues, global economic uncertainty and the need for agreed regional standards on product safety following recalls of Chinese-made goods in recent months.
""I am quite confident that they will be having a wide-ranging discussion on the economy,"" said a Canadian official.