BEIJING (Reuters) - The U.S. envoy for the North Korean nuclear dispute said on Friday that North Korea's rhetoric was deeply troubling and counterproductive, after Pyongyang threatened to attack South Korea if Seoul joined a new round of tightened U.N. sanctions.

U.S. Special Representative for North Korea Policy Glyn Davies told reporters in Beijing that he and his Chinese counterparts achieved a strong consensus that a new nuclear test would also be very troubling.

(Reporting by Sui-Lee Wee; Writing by Ben Blanchard; editing by Jonathan Standing)