UPDATE 1-Canada's Trudeau promises national prescription drug plan if re-elected

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HAMILTON, Ontario, Sept 23 (Reuters) - Canadian Prime Minister Justin Trudeau said on Monday that the Liberal Party would work with the provinces to set up a national prescription drug plan and to ensure that all Canadians have a family doctor if re-elected in next month's vote.

Trudeau gave no details on how the plan would be implemented or how much it would cost. Canada's universal healthcare system does not include universal coverage for prescription drugs, and primary care doctors are scarce in many areas.

"We're going to close the gaps in the healthcare system, and make sure people can get the care they need, when they need it most," Trudeau said at a campaign rally in Hamilton, a blue-collar city in southwestern Ontario.

Most Canadian patients now rely on private, employer-based insurance plans for drug coverage, while some are covered by government programs for the elderly, people with low incomes or very high costs.

The ruling Liberals are competing for left-of-center votes with the New Democrats and the Greens, both of which have promised comprehensive drug programs.

On the other hand, Conservative leader Andrew Scheer has said he would seek to close gaps in the current system. Successive Canadian governments and employers have been grappling with the rise of high-cost drugs.

Trudeau's Liberal government has already said a new federal drug agency will play some role in negotiating prices, but has yet to share details. Patented drug prices are among the highest in the world. (Reporting by David Ljunggren, Writing by Allison Martell, Editing by Steve Scherer and Andrea Ricci)