Mr Johnston was the only Western reporter based permanently in Gaza

The 44-year-old has not been seen since he was seized at gunpoint on his way home in Gaza City on 12 March.

Since then no public demands have been made by his kidnappers or information released on his whereabouts.

But the Palestinian Authority, the BBC and the UK government say that they are working as hard as possible to secure his release.

There is still no clear information about what state of physical or mental health the Gaza correspondent may be in.

His abduction has severely limited reporting of a key part of the Middle East story, much to the frustration of Palestinians in Gaza, BBC Middle East correspondent Tim Franks says.

There have been calls around the world for the journalist's release.

Last week, UN Secretary General Ban Ki-moon repeated his appeal for the immediate release Mr Johnston.

Mr Johnston joined the BBC World Service in 1991 and has spent eight of the last 16 years as a correspondent, including periods in Uzbekistan and Afghanistan.

He has lived and worked in Gaza for three years and was the only Western reporter permanently based in the often violent and lawless territory.