The loonie was trading 0.7% higher at 1.2649 to the greenback, or 79.06 U.S. cents, its biggest gain since Jan. 20. The currency traded in a range of 1.2646 to 1.2738, having touched on Friday its weakest intraday level in two weeks at 1.2748.

It's "normal business resumed" on the risk-on, reflation trade as nervousness dissipates about the surge in bond yields, said Robin Marshall, director of fixed income research at FTSE Russell.

Investors are betting that the rollout of COVID-19 vaccines will lead to global economic recovery, boosting the outlook for commodity-linked currencies like the Canadian dollar.

"I think you are going to continue to see some volatility around that trade because of how far we've come with government yields backing up and with currencies responding in that way to it," Marshall said.

The S&P 500 was headed for its best day since June 5 as bond markets calmed after a month-long selloff, while encouraging updates on vaccines and fiscal stimulus bolstered sentiment.

Canada sends about 75% of its exports to the United States, including oil. U.S. crude futures settled 1.4% lower at $60.64 a barrel on fears that Chinese oil crude consumption is slowing.

Canada's current account deficit narrowed to C$7.3 billion in the fourth quarter from a revised C$10.5 billion deficit in the third quarter, Statistics Canada said. Canada's fourth-quarter GDP data is due on Tuesday.

Canadian government bond yields were mixed across a steeper curve, with the 10-year up 1.6 basis points at 1.373%. On Friday, it touched its highest intraday since January last year at 1.501%.

(Reporting by Fergal Smith; Editing by Alistair Bell and Nick Zieminski)

By Fergal Smith