A speech by a North Korean diplomat at the Kennedy School of Government that had been tentatively planned for tomorrow has been cancelled after the State Department refused to grant the official a visa, the University said yesterday.

Pak Gil-yon, the North Korean ambassador to the United Nations, was slated to talk about “challenges in the region” from a North Korean standpoint, according to Kennedy School spokeswoman Melodie L. Jackson. The North Korean nuclear program would have likely been a topic of discussion, she said.

The Kennedy School’s Belfer Center for Science and International Affairs planned to co-host the event with the school, according to the South Korean state news service Yonhap, which first reported the story.

But Harvard never announced the speech because diplomatic issues had yet to be resolved, according to Jackson.

“This was a tentative event. The title hadn’t been finalized yet,” she said yesterday.

Because North Korea has no diplomatic relations with the United States, its ambassador to the United Nations is required to apply for permission to travel outside of New York.

“I know that we’ve certainly issued permission for travel in a number of other places around the country” said then-State Department spokesman Richard A. Boucher of the North Korean ambassador and his aides to the United Nations at a daily press briefing in 2004. “They’ve been out to California; they’ve been to other parts of the nation. So it’s not that unusual for us to issue permission for them to travel from time to time.”

Jackson said that visa issues come up once in a while and that it was not unheard of for a visa to be denied. She added it was the first time that she could recall a North Korean diplomat coming to Harvard for a speech.

The State Department did not respond to requests for comment.

Jackson said it was possible the forum could be scheduled for a later date.

—Staff writer Cyrus M. Mossavar-Rahmani can be reached at crahmani@fas.harvard.edu.