U.S. federal prosecutors are preparing new actions targeting Chinese firms that officials say are critical financial conduits for North Korea’s government, according to people familiar with the matter, an effort that could provide muscle to the Trump administration’s plans to rein in Pyongyang’s weapons program.

The Washington U.S. attorney’s office in May obtained warrants to freeze funds of Chinese firms that were processed through U.S. banks, alleging these firms help finance North Korea’s weapons program.

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