TORONTO, Feb 6 (Reuters) - The Canadian dollar cut earlier gains against the greenback to trade lower on Thursday after data showed the country's trade deficit was much larger than expected in December. Canada's trade deficit was C$1.66 billion ($1.49 billion) in December, the biggest gap since November 2012. At the same time, investors were taking in data south of the border that also showed the U.S. trade deficit widened at the end of last year. The Canadian dollar had been trading around session highs heading into the releases. Shortly after the data, the currency was at C$1.1100 to the greenback, or 90.09 U.S. cents, weaker than Wednesday's close of C$1.1080, or 90.25 U.S. cents.