Sen. John McCain predicted Sunday that Libyan leader Moammar Gadhafi is on the verge of falling from power.

“It’s a matter of hours if not days,” the Arizona Republican said on CBS’ “Face the Nation.” “And once our NATO forces, under the leadership of the British and the French and others, became more heavily engaged with the use of air power, I think it was something that was going to happen.”

The administration also believes “Gadhafi’s days are numbered,” Deputy White House Press Secretary Josh Earnest said in a statement announcing that President Barack Obama had been briefed Sunday morning on developments in Libya. Obama is vacationing with his family in Martha’s Vineyard in Massachusetts.

McCain has faulted the administration for not intervening sooner in the Libyan conflict. “I grieve a bit because this conflict didn’t have to last this long,” he said Sunday. “The United States’ air power could have shortened this conflict dramatically. And unfortunately we chose not to. We led from behind.”

Even so, Gadhafi’s downfall sends a message to other nations that have cracked down on their citizens, McCain said.

“This will send a message to Bashar Assad, it’ll send a message in Yemen, it’ll send a message to other dictators that their time is nearing the end,” he added. “This Arab Spring is echoing all over the world from Russia to China to Israel to — and being manifested in a lot of different ways.”

Obama called on Assad, Syria’s president, to resign last week and announced that the United States would impose new sanctions against the Middle Eastern country, which has violently cracked down on an uprising against Assad’s regime.