WASHINGTON, Aug. 24 (Xinhua)-- The United States on Friday accused Iran of playing a negative role in Iraq by sending lethal weapons to sectarian militants in the war-torn country.

    "We've made it very clear that Iranian activity inside Iraq has not been helpful," National Security Council spokesman Gordon Johndroe told reporters in Crawford, Texas, where U.S. President George W. Bush is vacationing.

    "According to our commanders on the ground, we see an increased flow of very deadly explosively formed projectiles. That is not playing a constructive role in Iraq," he said.

    "Those weapons supplied by Iranians to militias are responsible for the deaths of American soldiers. The support of those militias is responsible for the deaths of innocent Iraqis. It is an understatement to say that that kind of activity is not useful, nor helpful."

    The Bush administration has been accusing Iran of supporting sectarian militants in Iraq and trying to sabotage U.S. security gains in Iraq.

    Iran rejects the U.S. charges.

    It was reported that Washington has decided to designate Iran's Revolutionary Guard Corps, the country's 125,000-strong elite military branch, as a "specially designated global terrorist."