Foreign Secretary Miliband says claims against the workers have "absolutely no substance."
By JONNY PAUL, AP, LONDON
British Foreign Secretary David Miliband said Sunday that Iran would release without charge one of two British Embassy employees still being held in Teheran after seven others were freed last week.
Iran had claimed that eight had been released but Miliband's statement appeared to contradict that.
The British foreign secretary told the BBC that the claims against the staff had "absolutely no substance."
A lawyer for a ninth man, political analyst Hossein Rassam, says he has been charged with harming Iran's national security.
Iranian officials detained the embassy staff just over a week ago, accusing them of fomenting unrest.
All are Iranian nationals, and seven were released on June 29.
On Friday, the head of Iran's powerful Guardians Council had said the embassy staff being held would face trial.
Ayatollah Ahmad Jannati, who is close to Iran's supreme leader, Ayatollah Ali Khamenei, made the announcement during Friday prayers in Teheran.
"Naturally they will be put on trial, they have made confessions," Jannati had said. "In these incidents, their embassy had a presence. Some people were arrested."
The British Foreign Office had said it was very concerned and urgently seeking an explanation from Iran on the matter.
"We are very concerned at these reports and are investigating them," a Foreign Office spokesperson said. "The allegations that embassy staff were involved in instigating the recent demonstrations are wholly without foundation."
Protests were widespread across Iran following last month's presidential election amid claims the vote had been rigged in favor of incumbent President Mahmoud Ahmadinejad. At least 20 people were killed in the rioting and many more arrested.
Teheran has repeatedly accused foreign powers - especially Britain and the US - of stoking the unrest after the June 12 election. Last month Khamenei described Britain as the "most evil" of its enemies.
European Union governments have considered temporarily recalling their ambassadors to Iran in protest over the Britons' continued detentions.
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