WASHINGTON (AP) - A federal appeals court has ruled that the Federal Communications Commission lacks the authority to require broadband providers to give equal treatment to all Internet traffic flowing over their networks.

Tuesday's ruling by the U.S. Court of Appeals for the District of Columbia is a big victory for Comcast Corp., the nation's largest cable company. It had challenged the FCC's authority to impose so called ‘‘net neutrality'' obligations.

It marks a serious setback for the FCC, which needs authority to regulate the Internet in order to push ahead with key parts of its massive national broadband plan.