BEIJING (Reuters) - China said on Monday that U.S. plans to bolster missile defenses in response to provocations by North Korea would only intensify antagonism, and urged Washington to act prudently.

Chinese Foreign Ministry spokesman Hong Lei made the comments at a daily news briefing.

U.S. Defense Secretary Chuck Hagel announced plans on Friday to bolster U.S. missile defenses in response to "irresponsible and reckless provocations" by North Korea, which has threatened a preemptive nuclear strike against the United States.

(Reporting by Sui-Lee Wee; Writing by Ben Blanchard; Editing by Robert Birsel)