State regulators in North Dakota say they support a controversial pipeline that would carry oil from Canada to the Gulf of Mexico, though they want it constructed in a responsible manner.

TransCanada Corp.'s proposed 2,673-kilometre Keystone XL pipeline could carry oil from the Williston Basin in western North Dakota and eastern Montana to downstream markets, the Industrial Commission said in endorsing the project Tuesday.

"It is important that this pipeline be constructed and operated in a manner that will protect the citizens of the United States," the governor, attorney general and agriculture commissioner said in a letter to U.S. Secretary of State Hillary Clinton.

The proposed pipeline has drawn opposition from people who fear it will harm the environment. Calgary-based TransCanada says the $7 billion US project would meet strict environmental standards. The U.S. State Department is considering whether to approve the project. Hearings are being held this week in the six states the pipeline route would cross. A meeting was planned Thursday in Pierre, S.D.

North Dakota, which is now the fourth-largest oil producer in the United States, is not one of the states the pipeline would cross. The pipeline will pass through neighbouring Montana.

"As North Dakota continues to expand its oil production, we must also expand the distribution system," Gov. Jack Dalrymple said. "It's important that we have a system that can handle our growing Williston Basin production, and the Keystone pipeline can help do just that."

The Industrial Commission oversees the state's Oil and Gas Division, Oil and Gas Research Program and the North Dakota Pipeline Authority.