Leon Panetta, the US defence secretary, has made some strong remarks during his first visit to Iraq since taking the job, blaming Iran for the latest violence against US troops in the country.

His comments have infuriated some inside Iraq, as well as in neighbouring Iran. He even went as far as warning that his country would take unilateral military action against Shia groups armed by Iran.  

Around 46,000 US troops remain in Iraq, but they ended combat operations almost a year ago.

So, just how much truth is there to Panetta's accusations and what could be the repercussions of the unilateral action he has warned the US could take?

We also take a look at the armed Shia groups in Iraq and ask if Iran is really supplying them with weapons.

Inside Story with presenter Laura Kyle, discusses with guests: Raed Jarrar, an Iraqi-American political analyst and blogger; Sadegh Zibakalam, a professor of politics at Tehran Univeristy; and Arash Aramesh, an Iran researcher for US-based thinktank the Century Foundation.

This episode of Inside Story aired from Wednesday, July 13, 2011.