CALGARY, Alberta (Reuters) - Suncor Energy Inc (>> Suncor Energy Inc.), Canada's largest oil and gas company, reported a first-quarter operating loss on Wednesday as sagging crude prices outweighed record production at the company's oil sands operations in Northern Alberta.

Excluding one-time items, Suncor reported an operating loss of C$500 million ($397 million), or 33 Canadian cents per share. That is compared with an operating profit of C$175 million, or 12 Canadian cents per share, in the year-ago period.

Thousands of workers have been laid off and producers have slashed capital spending in the oil sands regions where Suncor mainly operates, helping drive down production costs over the last two years.

Net profit rose to C$257 million, or 17 Canadian cents per share, in the first quarter of 2016, compared with a loss of C$341 million, or 24 Canadian cents per share, boosted by a non-cash foreign exchange gain on debt revaluation.

Oil sands production rose to a record 453,000 barrels per day (bpd), compared to 440,400 bpd a year earlier, while cash operating costs for oil sands operations dropped to $24.25 per barrel, down 15 percent from a year ago, Suncor said.

Suncor's total upstream production, meanwhile, rose to 691,400 barrels of oil equivalent per day (boe/d), from 602,400 boe/d a year ago, buoyed by the takeover of rival Canadian Oil Sands Ltd (>> Canadian Oil Sands Ltd) earlier this year.

The Calgary-based company separately said it had reached a C$937 million ($744.2 million) deal to buy Murphy Oil Corp's (>> Murphy Oil Corporation) 5 percent stake in the Syncrude oil sands project, boosting Suncor's share in the joint venture to 53.74 percent.

The latest deal follows Suncor's all-stock acquisition of Canadian Oil Sands Ltd, ending a bitter hostile takeover battle that had been raging since October.

Chief executive Steve Williams said in a statement that the company will "continue to look for opportunities to grow our business through acquisitions, by adding assets that fit strategically at competitive valuations."

(Reporting by Julie Gordon and Nia Williams; Editing by Leslie Adler and Christian Schmollinger)