Rep. Tulsi Gabbard, D-Hawaii, said there is only one "viable" way to denuclearize an aggressive North Korean regime.

Following Pyongyang's latest intercontinental ballistic missile test this week, demonstrating a range not seen before, Gabbard advocated diplomacy, but with conditions.

"The only viable option that I see before us today is a diplomatic one, and that can only be pursued if two things happen," Gabbard said on CNN on Thursday.

"One is that we negotiate directly with North Korea and Kim Jong Un," she said, adding, "and secondly, in order for those negotiations to be successful, we have to understand why Kim Jong Un is holding on so tightly to those nuclear weapons because he sees them as his only deterrent from the U.S. coming in and trying to topple his regime."

Gabbard, who serves on the Armed Services and Foreign Affairs Committees, criticized past leaders on both sides of the aisle for allowing the escalating situation to get where it is currently.

She cited U.S. involvement foreign affairs, including in Libya and Syria, which created problematic situations for those countries' leaders, as examples that Kim might be looking at, leading to him to be wary of letting go of his regime's nuclear weapons program.