JOHANNESBURG, SEPT. 19 -- Namibia announced today that it will permit emergency food aid to be sent across its territory into areas of famine in southern Angola, Namibian state radio said. The decision could be a breakthrough in U.S.-led efforts to save thousands of Angolans threatened with starvation.

However, a senior official of the U.S.-backed Angolan rebel movement accused the Angolan government of stalling on a United Nations plan to send food shipments throughout the drought-stricken country, including rebel-held areas.

In an interview in Washington, Jeremias Chitunda, vice president of the National Union for the Total Independence of Angola (UNITA), said officials of the Soviet-backed government in Luanda evidently are "not willing to comply with promises they made to U.N. officials to allow cross-border shipments" for those starving in UNITA territory adjoining Namibia.

Namibian President Sam Nujoma signed several cooperation agreements with Angolan President Jose Eduardo dos Santos today in Lubango, Angola, Namibian radio said. Nujoma announced there that he would permit food shipments to Angola through Namibia.

The United States had pressed Namibia to allow relief agencies to transport emergency food aid via its ports, roads and railroads under international monitoring into southern Angola, where severe drought conditions have led to acute food shortages and put more than 2 million lives at risk, according to U.S. disaster relief officials.

It was not immediately clear whether Nujoma had agreed to permit relief agencies to ship food into territory in southeastern Angola controlled by UNITA.

Earlier, the Nambian government had told U.S. officials that it would not agree to the use of its territory for food shipments to rebel-held areas unless the Angolan government gave its assent.

But Nujoma accepted a proposal made by dos Santos to allow relief supplies to pass through Namibia "on condition that the operation was monitored by a joint Angolan-Namibian team," according to the South African Press Association.

"This is really not a new ray of hope," Chitunda said today. "An Angolan government-supervised program is really no program at all. We have to talk about deliveries to areas we control." For these, he said, supervision by the United Nations or some international organization is crucial.

In rebel territory, Chitunda added, the hardships of the two-year drought and food shortages were compounded by a government offensive launched late last year. Chitunda said food shipments through Namibia to government-controlled territory already have taken place.

A senior State Department official said in Washington Tuesday that U.N. officials had presented the Angolan government with a plan of action several weeks ago. He called the lack of a definitive Angolan response to that proposal "troubling, because the longer it takes, the more people are dying."

A spokesman of the Angolan government in New York did not respond to telephone calls seeking comment.

Peace talks between Angolan government and UNITA representatives are scheduled to resume in Portugal Monday.

At Portugal's suggestion, both the United States and the Soviet Union were prepared to send experts to help refine cease-fire issues. Chitunda said UNITA welcomes the experts' participation, but the Angolan news agency quoted Luanda's vice minister for foreign relations as saying Monday that U.S.-Soviet involvement at this point would be "premature."

"We don't know if that is the definitive word," the State Department official said. "It would really be regrettable if they felt that way."

Staff writer George Lardner Jr. in Washington contributed to this report.