Some fellow journalists called Mr. Lee’s reaction typical of his overstatements and said he had a persecution complex. But Mr. Lee claimed he was being kept from doing his work. He has difficulty getting into some events and must be escorted by a press office official in areas beyond those allowed by his new credentials, he said. The presence of a “minder,” he said, deters sources from speaking with him.

Mr. Dujarric said the new status was not meant to, and did not, prevent Mr. Lee from entering any areas for reporting.

“It’s not exactly the same access,’’ Mr. Dujarric said, “but if he has an issue, there is a staff of media liaisons to help him resolve the problem and get where he needs to go.”

The disciplinary action had nothing to do with Mr. Lee’s reporting, Mr. Dujarric said. Instead, it was his refusal to leave the room during the January meeting, which violated press guidelines, said Mr. Dujarric, who often must field Mr. Lee’s questions about press office issues as dozens of international journalists stand by, seeking updates on global issues.

“At some point, I might decide I’ve had enough, if it’s just about him,” said Mr. Dujarric, who did just that during a recent briefing, which began calmly enough, with correspondents asking for updates on stories about Congo, Gaza and Syria.

Then, Mr. Lee raised his hand and began grilling Mr. Dujarric on corruption topics and how he was being treated by the agency. Exasperated, Mr. Dujarric walked out of the room.

Much of Mr. Lee’s ire is directed at the United Nations Correspondents Association, the group to which most resident correspondents belong. Mr. Lee, a former board member, left the group in 2012 after running unsuccessfully for president against Giampaolo Pioli, an Italian journalist and the current president.