The Archbishop of York has made a fresh appeal for the release of missing BBC journalist Alan Johnston in which he tells of his own captivity under the regime of Idi Amin in Uganda.

Dr John Sentamu shared his experiences with an audience of national editors and broadcasters at the annual London Press Club Awards earlier in the week, describing how "the temptation to give up hope of release was always present".

"But my faith in Christ, my knowledge of the prayers being said on my behalf, these two things were instrumental in being able to survive each day in captivity," he said.

Dr Sentamu marked the fiftieth day of Johnston's captivity last week by leading clergy from the Diocese of York in prayer for his safe return and release.

He urged the faith community to pray for journalists like Johnston.

"Journalists, whether imprisoned or not, deserve the supportive prayers of the faith communities and the critical solidarity of all lovers of freedom. It is also true to say that those people persecuted for their religious faith deserve the attention of journalists," he said.

Earlier in the week, a group calling itself Jaish-e-al-Islam (The Army of Islam) sent a video to al-Jazeera in Gaza allegedly showing a picture of Mr Johnston's press card and demanding the release of Muslim prisoners detained in British prisons.

Al-Jazeera is due to broadcast a direct appeal for Johnston's release from Archbishop Sentamu in an interview he made with the network following the release of the video.

In his appeal, Dr Sentamu urges Johnston's captors to release him immediately and unharmed.

Dr Sentamu held a special vigil for Johnston last month to pray for an end to violence in the Middle East and especially for Johnston's release from his abductors in Gaza.