The report cited Syria's foreign minister Walid Muallem as telling UN chief Ban Ki-moon by phone that his country would "refuse any partial report published by the UN Secretary-General before the mission finished its work and the results of analyses of samples taken by the mission came to light".
UN inspectors are currently in Syria probing the alleged deadly gas attack on August 21 in Damascus suburbs, and are due to leave the country by Saturday morning before reporting directly to Ban.
Western governments have blamed the alleged attack on the regime of Bashar al-Assad, which has strenuously denied any involvement while pointing the finger of blame at "terrorist" rebels.
Questions have been raised about the quality of the intelligence linking Assad to the attack, and many say the West should wait for the UN analysis results before deciding to carry out its threat to launch punitive military action.