South Korea said it would hold a summit with North Korea for the first time in more than a decade, which investors took as a cue to sell the US dollar and buy commodity-linked currencies, which tend to outperform as the outlook for the global economy improves.

The price of oil, one of Canada's major exports, rose 0.6 percent and global stocks climbed, helped also by increasing resistance to US President Donald Trump's proposed tariffs on steel and aluminum.

A number of countries including Canada, which is the largest supplier of both metals to the United States, have threatened to retaliate to the tariffs.

At 9:16 a.m. EST (1416 GMT), the Canadian dollar was trading 0.6 percent higher at C$1.2890 to the greenback, or 77.58 US cents, its first advance since Feb. 23.

The currency traded in a range of C$1.2865 to C$1.2995. On Monday, it touched its weakest since July 5 at C$1.3002.

Gains for the loonie came after Mexican and US officials pushed on Monday to speed renegotiation of the North American Free Trade Agreement, with the United States floating the idea of reaching an agreement "in principle" in coming weeks to avoid political headwinds later this year.

Canada sends 75 percent of its exports to the United States. The Bank of Canada has said that uncertainty about the future of NAFTA is weighing increasingly on the outlook for Canada's economy.

The central bank has raised interest rates three times since July but is expected to leave its benchmark interest rate on hold at 1.25 percent in a policy announcement on Wednesday.