CALGARY -- TransCanada has inked a US$13-billion deal that would help expand its already vast natural gas pipeline footprint.

The deal with Columbia Pipeline Group would create one of the largest regulated natural gas transmission businesses in North America, the Calgary-based energy giant said Thursday.

Columbia operates a 24,000-kilometre pipeline network that stretches from New York to the Gulf of Mexico.

The deal, which includes the assumption of US$2.8 billion in debt, represents a rare opportunity to snap up assets in the Marcellus and Utica shale gas regions of the northeastern U.S., said TransCanada CEO Russ Girling.

"The assets complement our existing North American footprint which together will create a 91,000-kilometre natural gas pipeline system connecting the most prolific supply basins to premium markets across the continent," Girling said in a statement.

"At the same time, we will be well positioned to transport North America's abundant natural gas supply to liquefied natural gas terminals for export to international markets."

Company executives scheduled a conference call to discuss the deal Thursday afternoon.

TransCanada has made headlines in recent years for its challenges in building new crude oil pipelines, like Keystone XL and Energy East.

U.S. President Barack Obama nixed Keystone XL in November following a seven-year regulatory saga. National Energy Board hearings have not yet begun into the Alberta-to-Atlantic Energy East proposal, which has been facing mounting opposition from environmental groups and some Quebec politicians.