Blackman's wife, Claire, told the Telegraph she and her husband were now "cautiously optimistic".

She said: "It needs a little bit of time to sink in, but we are both delighted and incredibly grateful that the CCRC has given Al this chance.

"It's just the first step. We have got a long way to go and we can't afford to be carried away, but we are cautiously optimistic."

Lawyers for the 42-year-old former sergeant hailed the move as a “very significant” step and announced they would immediately mount a bail application to try to have him home by Christmas.

Jonathan Goldberg QC, leading Blackman’s legal team, said the odds had now turned in has favour, with nearly three quarters of cases reaching this stage eventually being quashed.