Iran's Revolutionary Guards Warn Protesters

Protesters in Iran will face the nation's "iron fist" if political demonstrations calling for the removal of the country's supreme leader do not end, a Revolutionary Guards commander has said. How much influence does the alternative security force have in Iran?

Also in the programme: the Indian priest who was held hostage by Islamist militants in Yemen for 18 months; and what will 2018 bring for Brexit negotiations?

(Image: Iranian students clash with riot police during an anti-government protest around the University of Tehran on 30 December 2017. Credit: EPA/STR)