Syrian President Bashar Al-Assad recently transferred two shipments of chemical weapons to Lebanon-based Hizbullah, the Syrian rebels are claiming.

Fahad al Masri, a spokesman for the Western-backed Free Syrian Army, told the Lebanese news website El Nashra on Thursday that “the Syrian regime managed to deliver shipments of chemical weapons to Hizbullah.”

He added that the weapons were delivered from an area near the capital Damascus and arrived in Lebanon sometime in the past several weeks.

The transfer of the weapons, al Masri told El Nashra, was coordinated by Syria and Iran.

“We cannot now provide more details but certainly all the international security agencies know this information,” he added.

The claims have yet to be verified by other sources.

Israel has in the past said that Assad transferring chemical weapons or other sophisticated weapons to Hizbullah would be a “red line” that would force it to act to protect its security.

The U.S. government, which has confirmed that the Syrian army used chemical weapons against rebel forces on multiple occasions, has said it will increase the “scope and scale” of its assistance to rebels in Syria in response.

At the same time, U.S. sources said last week that congressional committees are holding up a plan to send U.S. weapons to rebels fighting Assad, fearing such deliveries will not be decisive and the arms might end up in the hands of Islamist rebel groups.

President Barack Obama has been criticized for failing to act on his own “red line” on Syria. Obama has in the past said that use of chemical weapons by the Syrian regime would be a red line that “would change my equation.”

U.S. Joint Chiefs of Staff Chairman Martin Dempsey told a Senate panel Thursday that the Obama administration is deliberating whether to use military power in Syria.

The use of “kinetic strikes,” a military term that usually refers to missiles and bombs, “is under deliberation inside of our agencies of government,” he said.