Syria has shaken politicians in the West by hosting a meeting between two of the Middle East's most controversial leaders. 
 
Mahmoud Ahmadinejad, the Iranian president, and Sheikh Hassan Nasrallah, the leader of the Lebanese group Hezbollah, met in Damascus last week.

Both Syria and Iran support Hezbollah and that has been cited as a major issue in negotiations with the US.
 
In a joint news conference the Iranian president accused the US of trying to dominate the region saying that the US should not dictate relationships in the Middle East. 
 
And Bashar al-Assad, Syria's president, said that ties between Iran and Syria had never been closer.
 
In a further show of unity, they signed an agreement cancelling visa restrictions between their countries.
 
The agreement has been seen as a snub to the US as Hillary Clinton, the US secretary of state, said only last week that the US would like Syria to "begin to move away from the relationship with Iran, which is so deeply troubling to the region as well as to the United States".

Since the Obama administration took over, the US has been trying to develop its relationship with Syria - and recently it had seemed to be warming.

Have US overtures failed to break the three-decade Syrian-Iranian alliance? And how will it affect the nuclear issue?

Inside Story presenter Sami Zeidan is joined by Samir al-Taqi, the director of the Orient Center for International Studies in Damascus, Rime Allaf, an associate fellow at Chatham House specialising in Syria and Iran, and Kenneth Katzman from the Congressional Research Service.

This episode of Inside Story aired from Sunday, February 28, 2010.