Tehran - Iran is to free Sunday the one remaining detained British embassy staffer on bail, informed sources said.

Hossein Rassam, chief analyst of the British embassy who has been detained for more than three weeks, would be released later Sunday on a bail amounting to almost 100,000 dollars, the sources said.

Rassam - and the British embassy - are suspected of involvement in the recent popular protest demonstrations against alleged fraud in the June 12 presidential election. (dpa)