WASHINGTON (Reuters) - A U.S. appeals court on Tuesday struck down the government's latest effort to require internet providers to treat all traffic the same and give consumers equal access to lawful content, a policy that supporters call net neutrality.

The Federal Communications Commission did not have the legal authority to enact the 2011 regulations, which were challenged in a lawsuit brought by Verizon Communications Inc, the U.S. Court of Appeals for the District of Columbia Circuit said in its ruling.

"Even though the commission has general authority to regulate in this arena, it may not impose requirements that contravene express statutory mandates," Judge David Tatel said.

Although the three judge panel were unanimous about the outcome, one wrote separately that he would have gone even further in restricting the FCC's authority.

The FCC could appeal the ruling to the full appeals court or to the U.S. Supreme Court, or it could attempt to rewrite the regulations to satisfy the appeals court.

During the oral argument in September, Verizon's lawyer said the regulations violated the company's right to free speech and stripped control of what its networks transmit and how.

The eventual outcome of the dispute may determine whether internet providers can restrict some content by, for instance, blocking or slowing down access to particular sites or charging websites to deliver their content faster.

The FCC had no immediate comment on the ruling. Verizon also had no immediate comment.

(Reporting by David Ingram and Alina Selyukh; Editing by Will Dunham and Sofina Mirza-Reid)