As tensions mount with North Korea over the country's nuclear ambitions, Sen. Lindsey Graham (R-SC) is confident that President Trump will use any and all options to prevent the U.S. from being hit with a nuclear strike.

Graham, who joined Trump and Sen. John McCain (R-AZ) for a dinner at the White House on Monday, said on "America's Newsroom" today that a preemptive military strike against North Korea is a last resort, but Trump is at least keeping the option on the table.

He said he's on the same page as Trump and Homeland Security Secretary John Kelly in believing that it would be a huge mistake to allow North Korean dictator Kim Jong Un to have an intercontinental ballistic missile that could reach the U.S.

"There's two ways to stop it: Through diplomacy, using China to get them to stop developing ICBM, or to use military force," Graham said.

He added that he prefers diplomacy - as does Trump - but the critical issue is stopping North Korea before it's too late.

"He is not going to let this nutjob in North Korea develop a missile with a nuclear weapon on top to hit America," Graham said. "He doesn't want a war any more than I do, but he's not going to let them get a missile."

"If you're North Korea and you're betting that Donald Trump is all talk and no action, you're making a serious mistake."

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