N.Korea's suspected submarine-launched missile 'pushes the envelope'

North Korea fired what may be a submarine-launched ballistic missile (SLBM) on Wednesday, which would be the first test in three years of what had been a relatively young but rapidly progressing program to deliver nuclear weapons.

The launch comes hours after the North announced it would resume nuclear talks with the United States this weekend, potentially ending a months-long deadlock that followed a vow by leader Kim Jong Un and President Donald Trump to make progress.

The exact type of the missile and the launch platform remain unclear, but it appears to be a step that "pushes the envelope," said Joshua Pollack, a leading expert on nuclear and missile proliferation and editor of Non-proliferation Review.

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