The top U.S. military officer, Admiral Mike Mullen, says Iran has reduced its supply of weapons to insurgents in Iraq, but is still having an impact on violence there and in Afghanistan. 

In the past, U.S. officials accused Iran of supplying a significant amount of weaponry and ammunition to Iraqi insurgents, particularly the material, technology and training to build deadly high-powered roadside bombs.  But Admiral Mullen says that has changed, at least somewhat.

"They are clearly not shipping as much as they used to, but that does not mean they have stopped," he said. "They still are impacting the fights in both Iraq and Afghanistan, though not as significantly as they used to, or as the worst days in Iraq.  But they are still involved."

The admiral told reporters traveling home with him from Europe the reasons for Iran's apparent change of policy are not entirely clear.

"There is a view that they are waiting for the American forces to leave, on the one hand," he said. "I think there has certainly been a stronger approach in some cases on the part of Iraq with respect to Iran.  They certainly have seen the security improve dramatically in Iraq.  My view is they have a long view, and I think that is part of it as well.  Although, I could not tell you exactly what the specifics would be or exactly how they are looking at it."

The admiral, who is the top military adviser to President Barack Obama and Defense Secretary Robert Gates, also says he has not seen any indication of a broader change in Iran's military policy.

"From a security standpoint, not much has changed," he said. "My belief is they are still on a path to develop nuclear weapons.  They still sponsor terrorism.  They sponsor Hezbollah.  They sponsor Hamas.  They smuggle weapons to them."

Admiral Mullen says the Iranian election, and the protests and crackdown that followed, do not seem to have had any impact on the country's policies.  And he is still waiting to see the results of President Obama's offer to improve relations with Iran.