North Korea said today that it is seeking an unprecedented meeting of its top military officials with those of South Korea and the U.S. commander of United Nations Forces here.

The South Korean Defense Ministry confirmed receipt of a letter from North Korea's armed forces minister at the truce village of Panmunjom but refused to disclose its contents.

Later, the ministry, in a written statement, condemned the North's proposal which it earlier described as "unprecedented," as "a mere propaganda ploy . . . not worthy of attention."

North Korea's Pyongyang radio, in a broadcast monitored in Tokyo, reported that North Korea proposed to South Korean Defense Minister Lee Ki Baek that the first meeting of the senior military officials be held next month to attempt to relieve tensions in the Korean peninsula, which has been officially divided since 1948.

North Korean Armed Forces Minister O Chin U said the meeting, which he proposed to hold at Panmunjom, should be arranged through preliminary talks to be held June 27, also at Panmunjom, Pyongyang radio said.

An American diplomat, who asked not be be named, said North Korea had warned the U.N. Command that the letter would be delivered and that representatives of both South and North Korea had engaged in "negotiations over whom the letter should be addressed to."

"There was concern among U.S. and South Korean officials that the letter might be part of a propaganda offensive tied to talks in Lausanne," the U.S. official said. South and North Korean officials met earlier this month in the Swiss city to discuss staging in North Korea some of the events of the 1988 Summer Olympics, which Seoul will host.

North Korea, after opposing staging of the Olympics in Seoul, changed its stance to demand that it be allowed to cohost the 1988 Olympiad, which it regards as a potential international diplomatic triumph for South Korea.

Although the two halves of the divided nation last September exchanged visits of relatives separated by the country's split and have engaged in unsuccessful negotiations for exchanges in sports, economics and Red Cross affairs, no proposal ever had been made by either side for a meeting of the two nations' defense ministers or top military officials.

The letter, according to Pyongyang radio, used the phrase "top-level military meeting" without spelling out what officials might be involved, but specifically proposed including Gen. William J. Livsey, who commands 40,000 U.S. troops here under the auspices of the United Nations.