TC Energy Corp. has declared force majeure on crude oil deliveries at destinations in Texas on its Marketlink pipeline, citing power outages caused by severe cold weather in the state, three sources familiar with the matter said.

Oil producers, pipelines and refiners in Texas and New Mexico have halted operations as they grapple with a rare deep freeze, which left nearly two dozen people dead and knocked out power to millions.

The Marketlink pipeline has a capacity of 750,000 bbl/d and flows south from Cushing, Okla., to Nederland, Texas, according to Wood Mackenzie. The line is connected to the Keystone oil pipeline system, a key transporter of Canadian crude from northern Alberta to refineries in the U.S. Midwest.

A TC Energy spokesman did not immediately respond to a request for comment.

The company told shippers the night of Feb. 17 the system is still operational, but that they were facing issues making deliveries at Houston and Port Arthur, Texas, facilities due to power outages, according to the notice seen by Reuters.

More than 2 million bbl/d of pipeline capacity into the Gulf Coast was shut at some point on Feb. 15, according to WoodMac, as freezing temperatures gripped the Permian Basin of Texas and New Mexico, the top producing shale basin in the country.