Updated 12:38 p.m. ET, 12/15/2013
(CNN) - Sen. John McCain joined CNN's "State of the Union" from Kiev, Ukraine, on Sunday after the Arizona Republican addressed thousands of protesters who are angry over the Ukrainian government's decision to backpedal away from an agreement with the European Union.
McCain spoke about a range of issues happening around the globe, and suggested the Central Intelligence Agency was not truthful to Congress about former FBI agent Bob Levinson, who went missing in Iran seven years ago.
Here are five noteworthy points from the interview.
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1) McCain: More oversight needed of U.S. intelligence agencies
McCain said he was "confident we are doing everything that we can" to get former FBI agent Bob Levinson released from Iran, where he went missing seven years ago.
But the senator said he was disturbed at recent reports that Levinson was in fact working for the CIA in Iran, not conducting private business as officials have previously claimed.
"What disturbs me is apparently they did not tell the truth to the Congress. The CIA did not tell the truth to the American Congress about Mr. Levinson," he said. "If that's true, then you put this on top of things that our intelligence committees didn't know about other activities, which have been revealed by (NSA leaker Edward) Snowden - maybe it means that we should be examining the oversight role of Congress over our different intelligence agencies."
He added that any negotiations in Levinson's case should also include attempts to free other Americans who are believed to be in Iranian custody.
McCain also weighed in on the interim deal reached with international powers and Iran on the country's nuclear program. In exchange for easing of sanctions, Iran agreed to slow its nuclear development program as the world powers continue talks for another six months.
He said he thinks it's "very likely" the Senate will have a bill that restores some sanctions against Iran at the end of the six months if there's no result in further negotiations to dismantle Iran's program.
2) McCain says Putin is meddling
There's a political tug of war going on in the former Soviet republic of Ukraine, with the western part of the country at odds with the eastern part – which is more closely aligned with Russia - over a failed deal with the European Union.
Last month, Ukrainian President Viktor Yanukovych did not sign a trade agreement with the European Union, choosing instead closer economic ties with Moscow. The move sparked mass protests, with thousands pouring into the capital city, furious over the government's sharp turnaround from previous efforts to better integrate with Europe.
McCain showed up this weekend, along with Democratic Sen. Chris Murphy of Connecticut, to express support.
"This is a grass-roots revolution here," McCain told CNN chief political correspondent Candy Crowley. "It's been peaceful, except for when the government tried to crack down on them, and the government hasn't done that since. But I am praising their ability and their desire to demonstrate peacefully for change that I think they deserve."
Protesters say an EU agreement would open borders to trade and set the stage for modernization and inclusion. They accuse Yanukovych of preparing to take the country into a Moscow-led customs union.
Moscow has leverage that may have affected Yanukovych's decision last month to backpedal on the EU talks because Russia supplies Ukraine with natural gas.
McCain, a longtime critic of Russian President Vladimir Putin, said the recent pressure on Ukraine is one more example of Putin asserting his power in other countries.
there's no doubt that Ukraine is of vital importance to Vladimir Putin. One of - I think it was Kissinger, I'm not sure, said that Russian without Ukraine is an Eastern power; with Ukraine it's a Western power.
"This is the beginning of Russia. It was right here in Kiev," McCain said. "So Putin views it as the most highly important, and he has put pressure on Ukrainians. The price of energy, different kinds of activities, and the word is very clear that he has made certain threats. Whether he would carry those through or not, I don't know."
McCain also said Putin "is now a player in the Middle East, which he has not been since 1973," adding Putin is "realizing, thanks to our weakness, some of his ambitions."
Given that the U.S. is trying to work on a deal with Russia to remove Syria's chemical weapons stockpiles, Crowley asked McCain whether it was a good time to be taking on Russia.
"I don't think that we would be taking on Russia," McCain replied. "Look, these people (the protesters) love the United States of America, they love freedom, and I don't think you could view this as anything but our traditional support for people who want a free and democratic society."
"We're not talking about military action," he continued. "We're not talking about blockades. We're talking about the possibility of sanctions if they continue to brutally repress their people. That would require some action on our part, just because that's what the United States of America is all about."
3) 'Plead guilty'
McCain admitted Sunday he exaggerated when he compared President Obama's handshake last week with Cuban President Raul Castro to a handshake between Neville Chamberlain and Adolf Hitler at the start of World War II.
"I'm sure it was an exaggeration, Candy," he said. "If you want me to plead guilty here on CNN - guilty."
Obama faced a wave of criticism following his warm, though brief, greeting with Castro at Nelson Mandela's memorial service in South Africa.
"I think it was gross exaggeration," McCain said of the comparison. "But have no doubt that (the handshake) is of great propaganda value for the Cuban government, which is oppressive, repressive, continues to jail dissidents and continues to be one of the - probably easily the most repressive government in our hemisphere."
"I don't think you should shake hands with someone who continues to violate his own country's human rights," he continued. "It happened. But it is what it is. And I'm sure that Mr. Castro appreciated it."
The White House said the handshake was not preplanned, and officials pointed to Obama's comments in his speech that urged freedom in dictatorial societies.
4) McCain will vote for the budget bill
McCain said Sunday he'll vote for a compromise budget bill that would prevent another government shutdown.
"I hope it will pass the Senate," he said on CNN's "State of the Union." "We must not shut down the government again. We can't do that to the people of this country and my state."
The House approved the measure last week, but many GOP senators, raising a variety of concerns, are expected to vote against the bill. Despite their opposition, a few Republicans, including McCain, may help push the bill through the Senate.
McCain said he has spoken with military leaders who approve the deal because it "gives them relief from the harsh effects of sequestration."
Crowley asked if McCain would vote for the budget package as long as it stays the same.
"Yes," McCain said.
Final congressional approval would mark a rare win for bipartisanship and a step up for a Congress infected with political dysfunction and held in low public esteem, with midterm elections less than a year off.
5) 'This must be a huge embarrassment for China'
The execution of Kim Jong Un's uncle shows that the young North Korea leader is "dangerous," McCain said, noting the country's nuclear capabilities.
Because Jang Song Thaek, Kim's uncle by marriage, was believed to be a key figure in North Korea and a liaison between North Korea and China, McCain argued "this must be a huge embarrassment for China."
"It's very obvious this young man is capable of some very aberrational behavior, and given the toys that he has, I think it's very dangerous," McCain continued. "And you would think that the Chinese would understand that as well. They've got to rein this young man in, and they can."
- CNN's Nick Paton Walsh, Susanna Capelouto, Ted Barrett, Jethro Mullen, Tom Watkins, Susan Candiotti, and Catherine E. Shoichet contributed to this report.
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