Hardening position towards Iran, the US Secretary of State Gates says Iran may be to blame for the killing of US servicemen in Iraq.

Robert Gates who made the comment at a Pentagon news conference on Wednesday claimed,” What the Iranians are doing is killing American servicemen and women inside Iraq.''

This is while Gates did not provide any evidence to prove his claim against Iran.

Asked if General Odierno, General Petraeus and Admiral Fallon have difference of opinion on Iran, Gates said there was no disagreement among senior commanders -- including Fallon -- about the need to confront Iran over its conduct in Iraq.

"General Odierno and General Petraeus and Admiral Fallon were all in exactly the same position when it came to their views of Iranian interference inside Iraq,'' Gates said.

The Untied States is repeating its old allegations against Iran, accusing the Islamic Republic of exporting terrorism to Iraq, while Iran has repeatedly dismissed the allegations as baseless, saying the US claims lack evidence.