(AP) — Supporters and opponents of the Keystone XL pipeline in Nebraska are traveling to Washington to testify before a House subcommittee.

Norfolk Area Chamber of Commerce CEO Dennis Houston is scheduled to appear Thursday before the House Commerce Subcommittee, as is Ron Kaminski, the business manager for the Laborers Local 1140 in Omaha.

Jane Kleeb, executive director of Bold Nebraska, which opposes the pipeline, will argue that the project poses an unnecessary risk to Nebraska landowners.

Opponents are urging President Barack Obama to deny a federal permit for the proposed Canada-to-Texas oil pipeline, saying it doesn’t serve U.S. energy interests and would contribute to global warming. Supporters say the pipeline is by far the safest way to transport the oil from Canadian tar-sands deposits.