(Reuters) - Senator John McCain Friday called on the United States to recognize Libyan rebels as the true voice of the Libyan people and transfer frozen Libyan assets to them.

McCain, speaking to reporters while visiting the eastern rebel stronghold of Benghazi, also called for NATO to step up its air strikes against Muammar Gaddafi's military and said Western allies should provide rebels with training, weapons and command-and-control activities to help overthrow the Libyan leader.

"I would encourage every nation, especially the United States, to recognize the Transitional National Council as the legitimate voice of the Libyan people," McCain said. "They have earned this right and Gaddafi has forfeited it by waging war on his own people."

McCain, believed to be the first U.S. politician to visit Benghazi since the conflict broke out in late February, made the trip to Libya on his own.

McCain, the top Republican on the U.S. Senate Armed Services Committee, also voiced concern that the battle between Gaddafi's troops and rebel forces has reached a stalemate and said he was asking them what more the United States can do to help them.

"I fear a stalemate that could lead to the emergence of radical Islamic extremists," McCain said at a news conference broadcast on CNN.

The U.S. Treasury has frozen more than $34 billion in Libyan government assets thus far as part of a sanctions program aimed at putting pressure on Gaddafi's regime. McCain arrived in Benghazi after the United States announced that it would use armed drone aircraft against Gaddafi's forces.

(Reporting by Alexander Dziadosz in Benghazi and Kim Dixon, Lisa Richwine and David Lawder in Washington; Editing by Bill Trott)