KINSHASA, Zaire (AP) _ Air Excellence got no explanation when officials stopped its cargo flights to neighboring Angola. But the owners say they know why it happened: because of suspicions that powerful Zairians are running guns abroad even as Zaire struggles with an armed insurgency.

Air Excellence co-owner Phillipe Gonda says the company isn't involved. ``My conscience is fully clean,'' he said in an interview, describing the cargo he used to regularly ship for sale in Angola as humanitarian _ beer and food.

He believes the letter he received from airport officials, denying him permission to fly to Angola, was the product of rumors that his planes were carrying weapons to the Angolan rebel force known as UNITA.

Western governments and Angola's neighbors suspect the gunrunning is going on, and fear it could lead to renewed fighting in Angola, a country long divided by civil war where negotiators are trying to patch together a peace.

Details about the weapons trafficking are scarce. A senior Western diplomat, speaking on condition of anonymity, said it is known to involve Mobutu's entourage. A Zairian knowledgeable about both his country's elite and its government named several airlines believed to be involved. He also requested anonymity, saying making accusations means making powerful enemies.

Even Gen. Kikunda Ombala, whom the Western diplomat praised for trying to halt the weapons trafficking, refused to say why he had stopped flights to UNITA-controlled parts of Angola soon after he took on the job of overseeing Zaire's 24 airports in December.

``I made the decision _ that's it. There's no why,'' Kikunda told The Associated Press. ``We are putting things in order.''

Kikunda is believed to have responded to pressure from Western governments and from Zaire's neighbors.

For many Zairians, there is nothing shocking in reports that relatives and friends of President Mobutu Sese Seko were involved in weapons trafficking that could endanger Angolan peace efforts. They have been long convinced the country's elite was more interested in enriching itself than in the well-being of Zaire and the region.

In exchange for a share of the profits, members of Mobutu's entourage reportedly ensure that shipments of weapons from abroad handled by several companies aren't carefully scrutinized.

Gonda admits his airline is closely linked to one of the president's sons, Mobutu Kongulu.

Mobutu Kongulu is an army captain who spends most of his time overseeing a dozen businesses that range from imports to river shipping.

``He helps us with problems we have in the country _ everyone in this country has a protector,'' Gonda said.

Word high-ranking Zairians were helping UNITA re-arm is believed to have reached Angolan government officials. They retaliated by flying planeloads of Zairian dissidents who had been living in exile in Angola to Rwanda, from where they are believed to have been put at the service of Zairian rebel forces, according to the Western diplomat.

UNITA has pledged itself to peace in Angola, but has dragged its feet on agreements to disarm and demobilize. A UNITA spokesman, reached in Lisbon, dismissed reports the group was getting arms through Zaire.

``UNITA no longer has an army, we have no need for weapons,'' Jose Pedro said.

Since Zaire's own rebel war began in September, President Mobutu has spent most of his time at his villa in the rich man's playground of southern France, far from a homeland of impassable roads and jobless youth. He returned to Kinshasa last week, but seems no less distant from Zaire's problems, holed up in the handsome presidential mansion overlooking the Zaire River and surrounded by an army camp.

The elite presidential guard is one of the few Zairian army units that can count on regular pay checks. Other soldiers were notorious for supplementing meager wages by using their guns to rob civilians.

Zaire's army chief Gen. Mayele Lieko last week told reporters his soldiers lacked the equipment they needed to combat rebels who in the last seven months have taken control of much of eastern Zaire.