Iran nuclear crisis: Sanctions 'beginning to bite'
The US has said threats by Iran to restrict Gulf shipping in the event of further sanctions shows international pressure is having an effect.
The State Department said sanctions on Tehran over its nuclear programme were starting to bite and that Iran was trying to create a distraction.
Iran has conducted 10 days of exercises near the strategically vital Strait of Hormuz, test-firing several missiles.
James Reynolds reports.
03 Jan 2012