The Qatar-based al-Jazeera news channel has received a tape purportedly from the kidnappers of the BBC's Gaza correspondent Alan Johnston. It contained no new pictures of Johnston, but showed a picture of his BBC ID card.
The tape included a demand for the release of Muslim prisoners in British jails, and readings from the Koran.
Johnston, 44, was abducted in Gaza City on 12 March.
The tape was delivered to al-Jazeera in Gaza and on behalf of a group calling itself Jaish al-Islam (Army of Islam).
The BBC on Wednesday published a statement, saying: "We are aware of the tape released by the Army of Islam concerning our Gaza correspondent, Alan Johnston. We have no comment on the demands made of the British government in the tape - we remain concerned for Alan's well-being and call for his immediate release."
The tape included one specific demand, the release of Abu Qatada, a Palestinian born cleric who is suspected of close links to al-Qaeda and is currently held by the British government as a threat to national security.
