A U.S. expert on Korean affairs who recently visited Pyongyang says he does not believe any changes have been made in the North’s attitude toward resolving its nuclear issue.

Jack Pritchard, the president of the Korea Economic Institute, made the comment to reporters after wrapping up a four-day trip to the North and arriving in Beijing on Tuesday with two other American experts.

Pritchard said his group went to Pyongyang for research purposes and did not carry with it an official message from the U.S. government to North Korea. He added that Pyongyang also did not ask that any messages be delivered to Washington.

Though Pritchard and his group’s North Korea visit was for research purposes, attention is being drawn to their visit as it came before U.S. special representative for North Korea policy Stephen Bosworth will visit Pyongyang on December eighth.