JAKARTA, Indonesia — A top U.S. general said Tuesday there was no evidence the Iranian government was supplying Iraqi insurgents with highly lethal roadside bombs, apparently contradicting claims by other U.S. military and administration officials.

Gen. Peter Pace, chairman of the Joint Chiefs of Staff, said U.S. forces hunting down militant networks that produced roadside bombs had arrested Iranians and that some of the material used in the devices were made in Iran.

"That does not translate that the Iranian government per se, for sure, is directly involved in doing this," Pace told reporters in the Indonesian capital, Jakarta. "What it does say is that things made in Iran are being used in Iraq to kill coalition soldiers."

His remarks might raise questions on the credibility of the claims of high-level Iranian involvement, especially following the faulty U.S. intelligence that was used to justify the invasion of Iraq in 2003.

Three senior military officials in Baghdad said Sunday that the highest levels of Iranian government were responsible for arming Shiite militants in Iraq with the bombs, blamed for the deaths of more than 170 U.S. troops

Asked Monday directly if the White House was confident that the weaponry is coming on the approval of the Iranian government, spokesman Tony Snow said, "Yes."

Iran on Monday denied any involvement.

"Such accusations cannot be relied upon or be presented as evidence. The United States has a long history in fabricating evidence. Such charges are unacceptable," Foreign Ministry spokesman Mohammad Ali Hosseini told reporters in Tehran.