The chief of the U.N. nuclear agency confirms that traces of uranium were found at a suspected Syrian nuclear site, but says their source is not clear.

The International Atomic Agency (IAEA) director Mohamed ElBaradei Monday said at a conference in Dubai that a report due later this week on Syrian nuclear activity is inconclusive.  He said the uranium traces do not indicate whether there was a nuclear reactor at Syria's al-Kibar facility.

ElBaradei also urged more cooperation from both Syria and Israel, which bombed al-Kibar last year.

News agencies last week quoted unnamed diplomats close to an IAEA inquiry as saying inspectors found traces of uranium in samples from the rubble of the complex.

The Syrian government has dismissed the disclosures as politically motivated.  Syrian officials say any traces of uranium could have been left by Israeli bombs.

Israel bombed al-Kibar because it said it believed it was an almost-completed secret nuclear plant.  Syria denies building a reactor or hiding any nuclear activity.

The IAEA is drafting a formal report on Syria to be discussed during an agency meeting later this month.

Some information for this report was provided by AFP, AP and Reuters.