U.N., U.S. Say No Proof Chemical Weapons Used in Syria

U.N. investigators into rights abuses in Syria stressed Monday they had no conclusive proof that either side in the conflict has used chemical weapons, after a team member cited "concrete suspicions" that rebels have used sarin gas.

"The Independent International Commission of Inquiry on the Syrian Arab Republic wishes to clarify that it has not reached conclusive findings as to the use of chemical weapons in Syria by any parties to the conflict," the commission said in a statement.

Meanwhile, the United States said it was "highly skeptical" of an assertion that Syrian rebels had used chemical weapons, after a U.N. human rights investigator suggested the opposition had deployed sarin gas.

"We find it highly likely that any chemical weapon use that has taken place in Syria was done by the Assad regime. And that remains our position," said White House spokesman Jay Carney.

Late Sunday, Carla del Ponte, a former war crimes prosecutor and a member of the commission, told Swiss public broadcaster RSI that "according to the testimonies we have gathered, the rebels have used chemical weapons, making use of sarin gas."

She acknowledged there was "still not irrefutable proof, (but) very strong suspicions, concrete suspicions that sarin gas has been used... by opponents, by rebels, not by government authorities."

Her comments come amid growing Western suspicions that Assad's regime has used chemical weapons in the 26-month conflict and follow Israeli raids on military sites near Damascus over the weekend.

The commission of inquiry did not mention del Ponte's comments specifically, only stressing that it was "not in a position to further comment on the allegations at this time".

The commission's Brazilian chief Paulo Sergio Pinheiro reminded "all parties to the conflict that the use of chemical weapons is prohibited in all circumstances under customary international humanitarian law".

Set up two years ago at the behest of the U.N. Human Rights Council, the commission has so far been unable to gain access to Syria as Damascus has ignored repeated requests for entry.

Instead, it has interviewed over 1,500 refugees and exiles as a basis for its reports and its charges that both the government forces and their allies and opposition forces have committed war crimes in Syria, where more than 70,000 people have been killed since the violence exploded in March 2011.

The commission is set to publish its next report on the situation in Syria at the end of May and will present its findings to the Human Rights Council during its next session in June.