Member of the opposition accuses U.S. of using talks to buy time . The sides could reach a deal in week , says Israeli minister . Iran 's proposal was one with a new `` level of seriousness , '' Iran official says . P5+ hundreds , Iran issue joint statement for first time , but it 's short on details .
Member of the opposition accuses Iran of using talks to buy time . The sides could reach a deal in several months , says Iranian minister . Iran 's proposal was one with a new `` level of seriousness , '' U.S. official says . P5+1 bloc , Iran issue joint statement for first time , but it 's short on details .