Obama Warned Trump Before He Left Office: North Korea is White House's Biggest Problem

Before he left office, Barack Obama told President Donald Trump that North Korea's growing missile program and march toward developing a nuclear weapon was the most urgent problem he would face, the New York Times reports.

The report also said Obama three years ago ordered Pentagon officials to increase cyberattacks against the missile program in an attempt to disrupt test launches early on, a directive that seemingly turned out well for the U.S. as a large number of North Korea's military rockets later exploded or veered off course.

But the successful launch of a ballistic missile test on Feb. 11, the first since Trump took office, and claims by North Korea's leader Kim Jong-un that his country was close to testing an intercontinental ballistic missile, has put the U.S. on edge.

The threats, the Times reports, are "far more resilient than many experts thought."

The UN has tried to halt North Korea's testing by placing sanctions on the North, most recently imposing a cap on coal exports. But that hasn't stopped Kim as his country's nuclear capabilities have sharply increased.

Trump's aides told the Times that "everything is on the table," including pre-emptive military strike options, putting American tactical nuclear weapons back in South Korea and freezing the Kim family's assets.

Trump on Twitter in early January said North Korea's claim that is was in the final stages of developing a nuclear weapon capable of reaching parts of the U.S. was an empty threat and that it would "never happen."

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