Delivery volumes rose 24 percent in the company's Canadian Mainline gas pipeline system and 14 percent in the NGTL system in Western Canada in the first three months of the year.

"An unseasonably cold winter resulted in strong demand for our critical pipeline and power infrastructure assets," Chief Executive Officer Russ Girling said in a statement.

Girling said the recently completed Keystone Gulf Coast crude pipeline between Cushing, Oklahoma, and the U.S. Gulf Coast, expected to carry on average 520,000 barrels per day in 2014, had also helped TransCanada increase earnings.

Comparable earnings, which exclude most one-time items, rose to C$422 million ($385 million), or 60 Canadian cents per share, in the first quarter ended March 31, from C$370 million, or 52 Canadian cents per share.

The company said net income attributable to common shareholders fell to C$412 million, or 58 Canadian cents per share, from C$446 million, or 63 Canadian cents per share, a year earlier. The year-earlier quarter included C$84 million of net income related to an impact of a regulatory decision on the company's Canadian Mainline system.

TransCanada is best known for its controversial $5.4 billion Keystone XL oil pipeline, which has been awaiting U.S. approvals for more than five years amid bitter opposition from environmental groups.

The U.S. State Department said in April it would delay deciding whether the pipeline is in national interest until a legal dispute is settled in Nebraska.

TransCanada said it had invested $2.3 billion in the oil pipeline project, as of March 31 and was disappointed with the latest delay.

"Our view is there really isn't a reason for this delay at the current time. We would hope we can work through these issues as quickly as we possibly can and get the process to the point of a decision," Girling said on a conference call in Calgary.

On Friday, Natural Resources minister Greg Rickford said Canada was not considering a challenge under the North American Free Trade Agreement if the pipeline is ultimately blocked.

TransCanada, which also owns a major stake in Canada's largest nuclear facility in addition to its network of pipelines, said revenue rose 28 percent to C$2.88 billion.

Funds generated from operations rose 20 percent to C$1.1 billion.

The company's shares closed nearly flat at C$51.17 on the Toronto Stock Exchange.

($1 = 1.0976 Canadian Dollars)

(Reporting by Scott Haggett and Nia Williams in Calgary and Ashutosh Pandey in Bangalore; Editing by Sriraj Kalluvila and Lisa Shumaker)