WASHINGTON - US Defense Secretary Robert Gates on Sunday defended the military operation in Libya, saying President Barack Obama didn't break the War Powers Act in handling the conflict. He also said cutting off fund to the operation would be a "mistake."

Speaking to "Fox News Sunday," Gates said he was working with the National Security Staff shortly after the War Powers Act was passed in 1973, and "I believe that President Obama has complied with the law, consistent in a manner with virtually all of his predecessors. I don't think he's breaking any new ground here."

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Gates said from the US standpoint, US service members are " involved in a limited kinetic operation. If I'm in (Libyan leader Muammar) Gadhafi's palace, I suspect I'd think I'm at war."

According to US constitution, Congress has the right to declare wars. The 1973 War Powers Act prohibits US armed forces from being involved in military actions for over 60 days, with a 30-day withdrawal period, without an authorization of the use of military force or a declaration of war. Congressmembers have been demanding the administration to seek approval for continued participation in the conflict as the 90 days for US military to take part in Libya mission are up Sunday, or they would cut off funds for the mission.

Gates warned that cutting off funds would not be the right thing to do, saying "we've been through this on a number of occasions... where Congress has threatened to cut off funding in Iraq and on several occasions and so on," he said. "Frankly, I think cutting off funding in the middle of a military operation when we have people engaged is always a mistake."

The White House on Friday brushed aside the 90-day deadline, saying it is under the threshold of War Powers Act, and therefore needs no Congressional greenlight.