France, Germany and Britain have written to the United Nations to say they are ready to reinstate sanctions on Iran if it does not return to negotiations with the international community over its nuclear programme.

The UK, France and Germany have told the UN they are ready to reimpose sanctions on Iran over its nuclear programme if it fails to resume talks by the end of August. The three countries, known as the E3, said they were prepared to trigger a "snapback" mechanism - meaning previous sanctions would be reinstated - unless Iran resumes negotiations.