Jan 7 (Reuters) - Futures for Canada's main stock index

edged up on low volumes on Tuesday, helped by higher commodity

prices, while investors weighed the impact of a potential shift

in political power after Prime Minister Justin Trudeau announced

his plan to resign.

March futures on the S&P/TSX index were up

0.21% as of 6:40 a.m. ET (1140 GMT).

Trudeau said on Monday he would step down in the coming

months after nine years in power, bowing to pressure from

lawmakers alarmed by his Liberal Party's miserable showing in

pre-election polls.

The Toronto Stock Exchange's S&P/TSX composite index

fell following the announcement, ending a three-day

gaining streak.

Oil prices climbed in the day, as fears

of tighter Russian and Iranian supply due to escalating Western

sanctions lent support.

Gold prices also edged higher, helped by a weaker

U.S. dollar.

On Tuesday, investors will be focused on the December Ivey

Purchasing Managers Index (PMI) data - a vital barometer of the

Canadian economy's health - scheduled for release at 10:00 a.m.

ET.

Friday's employment data may also offer clues on the Bank of

Canada's interest rate cut trajectory.

Across the border, the key U.S. nonfarm payrolls figures are

also due later in the week and any signs of resilience in the

economy are likely to push back expectations on the pace of the

Federal Reserve's monetary easing cycle this year.

In corporate news, Canadian waste management company GFL

Environmental ( GFL ) said it would sell its environmental

services division to Apollo Global Management ( APO ) and BC

Partners in a deal valued at C$8 billion ($5.59 billion).

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($1 = 1.4311 Canadian dollars)