Washington needs to "make sure that Kim Jong Un knows that if he acts in an aggressive fashion, the price will be extinction," McCain said on CNN's "State of the Union."
The Arizona Republican called for a strategy on North Korea that involved increasing missile defense and other defensive capabilities in South Korea, doing more to pressure China, and considering the deployment of nuclear weapons to the Korean Peninsula. McCain's remarks
came in his first nationally televised interview
since being diagnosed with brain cancer in July.
"The Korean defense minister just a few days ago called for nuclear weapons to be redeployed," McCain told anchor Jake Tapper, adding he thought "it ought to be seriously considered."
He said China was not doing enough to curtail its support of North Korea and that the US should use economic leverage to influence Beijing.
"I also think that we've got to tell the Chinese, it will hurt the United States if we lose some trade with you, but I'm telling you now, something is going to have to change," McCain said.
North Korea recently announced it had tested its most powerful nuclear weapon yet and has continued to conduct missile tests, all in defiance of the international community. President Donald Trump has responded to the moves with condemnation and in August threatened
"fire and fury like the world has never seen" on North Korea should the rogue nation continue to threaten the United States.
More military spending
In the interview, McCain slammed an agreement Trump made last week with Democratic leaders to tie funding for hurricane relief to a three-month extension of spending and suspension of the debt ceiling.
He blasted the legislative package in particular for not increasing defense spending.
"The agreement that they made is basically devastating to national defense," McCain said.
The measure passed
the Senate with 17 "no" votes
-- all of them Republicans, including McCain -- shortly after Trump made the agreement with Senate Minority Leader Chuck Schumer and House Minority Leader Nancy Pelosi.
"This was not an exercise in bipartisanship," McCain said Sunday. "The Republican leaders, (House Speaker Paul) Ryan and (Senate Majority Leader Mitch) McConnell, were surprised to hear that he had cut this deal with Chuck and Nancy."
McCain said the current level of defense spending was undermining the military's readiness and service members' safety, and he linked the spending issue to recent Navy incidents
"I believe my first obligation as chairman of the Armed Services Committee is to make sure the men and women who are serving in our military have everything they need," McCain said. "Under this agreement, they not only don't have everything they need, their lives are in greater danger."
McCain pointed out it was Trump who campaigned repeatedly on building up the military.
"This is a President that campaigned and said, 'I'm gonna rebuild the military, we're gonna increase that,'" McCain said.