"We have put a great team together for our talks with North Korea. Meetings are currently taking place concerning Summit, and more. Kim Young Chol, the Vice Chairman of North Korea, heading now to New York. Solid response to my letter, thank you!" Trump wrote in a tweet.

General Kim Yong Chol landed at Beijing airport on Tuesday and will continue on to New York the following day after talks with Chinese officials, South Korea's Yonhap news agency reported earlier, quoting diplomatic sources.

The trip is part of a flurry of diplomacy as preparations gather pace for the on-again, off-again summit between Trump and North Korea's leader, scheduled to take place in Singapore on June 12.