'Tough road ahead' for US over Iran, says ex-Bush aide

The clock is ticking down to a Tuesday deadline set to reach a deal over Iran's nuclear programme.

For days, top diplomats from six world powers have been meeting with their Iranian counterparts - with the goal to hammer out a framework so that a final accord can be reached by the end of June.

Stephen Hadley, who served as President Bush's National Security Advisor from 2005 to 2009, asserts that those issues along with ongoing unrest in parts of the Middle East may take the negotiations beyond the June deadline.

"I think the real question is what is the United States going to do to address this meltdown in the region," Mr Hadley told the BBC's Katty Kay.