The invasion force numbered about 4,000, nearly all veterans of the Ugandan Army, General Kagame said in an interview today.

Uganda has denied assisting the rebels, and Mr. Kagame said today that the Ugandan Government had actually made it more difficult for the Rwandans to reach the border.

But the Rwandan rebels fought the early stages of the war from bases in Uganda, according to a report, issued in January, by the Arms Project of Human Rights Watch. It said Uganda was the main source of weapons to the Rwandan Patriotic Front.

The report said France, Egypt and South Africa supplied weapons to the Hutu-led Government Army. Arms Embargo Blamed

The former Government army has placed the blame for its defeat primarily on the arms embargo imposed by the United Nations in May. But a commander who was here as part of the French intervention in July and August, Lieut. Col. Erik de Stabenrath, said that while the embargo deprived the Government of heavy weapons, Government soldiers had plenty of ammunition when they fled.

"They could have stood the lines for months, if they had had the will to fight," the colonel said, adding that the Government troops had been defeated because they were poorly led.

The Government militias, which terrorized civilians and massacred tens of thousands of Tutsi, basically fled without fighting. Colonel de Stabenrath said many officers of the former Government forces felt they were betrayed by their political leaders, who adopted the brutal policies that led to their isolation.