Senior commanders in the United Nations peace-keeping force in Yugoslavia were still at loggerheads with Nato yesterday over reports that military cargo aircraft have been secretly dropping supplies to the Bosnian army at Tuzla.
The drops, on four occasions this month, were seen by about 20 UN observers, including the British head of the Unprofor intelligence unit, known as G2. But Nato - its Awacs radar reconnaissance planes are supposed to monitor the no-fly zone over Bosnia - says it has no evidence of the flights. The row is the most serious rift yet between the two and will further undermine the credibility of the UN operation in Bosnia if, as senior UN commanders are reported to suspect, the US is clandestinely resupplying the Bosnian army with hi-tech weaponry.
Senior Western sources said on Saturday that the Nato Secretary General, Willy Claes, is expected to make a statement today. One source admitted, however, that if there is an agreed UN-Nato statement one side will have to back down. At the moment there is no sign of that.
A senior Western military source said: "If the US is supplying the Bosnia government, no one in [Nato] knows but then the US wouldn't tell them. It would have to be deniable, but if it comes out quite a few people will walk out. It would be so embarrassing."
UN observers say that on 10, 12, 17 and 23 February "transport type aircraft of C-130 or like size" were heard near West Tuzla airbase between 6 and 9pm. The planes, escorted by fighter aircraft, appeared to be making a low-level parachute drop, a manoeuvre performed only by US, British or French air forces.
According to a report by Lieutenant-General Bertrand de Lapresle, the UN commander in former Yugoslavia, the incidents on 10 and 12 February were assessed to have been "two clandestine resupplies" of "high-value/high- technology guided missiles or perhaps surface to air missiles". Nato has denied all knowledge of the flights and questioned the reports' accuracy.
What has infuriated UN commanders is that whereas Nato has previously accepted UN reports of flights and included them as valid sightings in its own reports, this time Nato has gone out of its way to discredit them.
UN officials are reported to suspect a US clandestine operation in which the Nato Awacs were told not to fly at certain times, the mystery aircraft gave them the "friendly" signal, or the CIA, knowing the flight pattern of the Awacs, timed the flights to coincide with a blind spot. Sources say there is speculation a proxy air force is being used, possibly Turkish.
According to the Washington Post last Tuesday, Nato officials said the Awacs were not flying on 10 or 12 February. Yesterday, however, a Nato spokesman said the planes would almost certainly have been covering the airfield and would have spotted a fixed-wing aircraft.
Senior US officials deny any US aircraft are involved in secret flights.One suggested that if the flights were real, they might be from a Muslim country friendly to Bosnia such as Iran. He dismissed the idea that Turkey might be involved as "dubious". But the official also admitted it was not in the Americans' interest to impose the arms embargo and the administration, under pressure from Congress, wants it lifted.
President Bill Clinton must stick by the UN and his allies or give in to Congress - unless he can make the arms embargo irrelevant by ensuring the Bosnians have what they need, or at least can hold out until the UN withdraws and the embargo is lifted.