Washington (CNN) -- A U.S. official confirms a report that Iran has transferred a sophisticated defensive radar system to Syria.
The Wall Street Journal first reported the transfer on Thursday, citing Israeli and U.S. sources. The article quoted the sources as saying the radar in Syria could limit Israel's ability to launch a surprise attack against Iran's nuclear facilities and increase the accuracy of Hezbollah's missiles, while bolstering the group's defenses.
The Israeli military, in a statement to CNN, warned about extensive and growing military cooperation between Iran and Syria, saying that Iran "considers both Syria and Hezbollah to be integral parts of its deterrent and advance warning capabilities.
"Iran is engaged in developing Syrian intelligence and aerial detection capabilities and Iranian representatives are present in Syria for that express purpose," the military statement said. "Radar assistance is only one expression of that cooperation."
State Department Spokesman P.J. Crowley could not confirm the transfer had taken place, but said the report raises eyebrows because of the military relationship between Syria and Iran.
"We don't believe that Iran's designs for the region are in Syria's best interest," Crowley said.
While he said countries have a right to protect themselves with radar systems the United States is concerned about the transfer of technology to Hezbollah.
"Providing advanced technology to Syria with the prospect it could again change hands is an ongoing concern to us," Crowley said.
Another U.S. official who is not authorized to speak for attribution said, "Iran continues to flex its muscles as a regional player" and added the latest developments bear close watching. "No one wants things to happen that could heighten tensions in the Middle East or possibly lead to instability in this part of the world. The stakes are too high," said the official.
Ahmed Salkini, a spokesman for the Syrian embassy in Washington, called the story "unfounded."
"Israel's strategy constitutes deviating world attention from the crimes it commits in the occupied Palestinian territories and portrays instead Iran as being the major threat in the region by frequently putting out fabricated stores," Salkini said. "Any time the world focuses on Israeli crimes they pull another stunt to try to shed the light again on Iran instead. "
"Even such a fabricated radar system pales in comparison to the vastly superior nuclear and conventional weapons arsenal that Israel has,' Salkini said."
CNN's Kevin Flower contributed to this report