Iran nuclear talks: 'Hurdles remain' as deadline looms
31 March 2015 Last updated at 06:57 BST
Talks have resumed in Switzerland ahead of Tuesday's deadline for a preliminary nuclear deal with Iran.
Foreign ministers from six world powers are meeting their Iranian counterpart, amid hopes of a breakthrough after almost 18 months of negotiations.
They want to impose limits that would prevent Iran from producing enough fuel for a nuclear weapon within a year.
Iran, which insists its nuclear programme is peaceful, wants to see crippling sanctions lifted in return.
Ben Bland reports.