President Trump said Wednesday that he has years to reach an agreement with North Korea to rid the country of nuclear weapons, reversing the position he took a year ago that Pyongyang had to disarm rapidly.

“I don’t want to get into the time game,” he said at a news conference late in the day, after serving as chairman of a United Nations Security Council meeting on nuclear proliferation.

“I got all the time in the world,” Mr. Trump said. “I don’t have to rush it.”

Mr. Trump’s statement came despite satellite photographs and other evidence that have led American intelligence agencies to conclude that North Korea continues to produce nuclear fuel and fabricate it into weapons. American officials estimate that the country now has between 20 and 60 nuclear weapons, and the number may be rising.

But Mr. Trump argued that the halt in nuclear and missile testing by North Korea — and a series of private letters exchanged with Kim Jong-un, the country’s leader — had taken the urgency out of the disarmament issue.