China's U.N. envoy says Pelosi visit to Taiwan would undermine U.S./China ties

China's envoy to the United Nations said on Monday that a visit by U.S. House of Representatives Speaker Nancy Pelosi to Taiwan would undermine China-U.S. relations.

China's U.N. ambassador Zhang Jun also told a briefing that such a visit by Pelosi would be provocative, and not comparable to the last time a U.S. House speaker visited the island claimed by Beijing in 1997.

Pelosi was set to visit Taiwan on Tuesday, three sources said, as the United States said it would not be intimidated by Chinese threats to never "sit idly by" if she made the trip.