The sister of a British journalist being held by Islamic State militants has appealed to his captors to reopen dialogue aimed at freeing him.

In a statement Jessica, the sister of John Cantlie challenges the version of events Islamic State present through her brother in a series of propaganda videos.

Her appeal comes after her terminally ill father asked Islamic State militants to return his son to safety earlier this month.

I am Jessica, John Cantlie’s sister. I am talking on behalf of the head of the Cantlie family. My father, Paul, is terminally ill and incapacitated. We, John’s family, want to address Islamic State, who are holding him.

Jessica Cantlie

John Cantlie has been held captive by militants since 2012 and has appeared in another propaganda video - the third in a series called Lend Me Your Ears.

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