Iran's leading dissident cleric, Grand Ayatollah Hossein-Ali Montazeri, has said the seizure of the American embassy in Tehran after the Islamic Revolution in 1980 was wrong.
By Sadeq Saba
BBC regional analyst
This is the first time that a prominent leader of the Iranian revolution has made such an admission.
The elderly cleric made a vocal return last week
Ayatollah Montazeri, who was once designated as Ayatollah Khomeini's successor, called for an immediate resumption of relations with Washington.
The ayatollah, who was released from five years of house arrest in January, made the comments in an interview with a foreign newspaper.
Former leader Ayatollah Khomeini once described the seizure of the American embassy in Tehran as Iran's second revolution. But now his closest ally calls the move a big mistake.
Source of friction
This is a significant revision of the events of the Islamic Revolution.
It is widely believed that the occupation of the US diplomatic mission is the root cause of the continuing hostility between Tehran and Washington.
Ayatollah Montazeri has urged the Iranian Government to resume ties with the US and also criticised Iran's President Mohammad Khatami, for failing to fulfil his promises.
Ayatollah Khomeini led the revolution in 1979
Mr Khatami's inaction, the ayatollah went on to say, has disappointed the Iranian people.
Ayatollah Montazeri, who is in his early 80s, said the people have every right to choose their rulers and criticise their action.
He pointed out that even the prophet Mohammad did not establish his rule before being accepted by his people.
The ayatollah attacked the existence of political prisoners in Iran and said Islam was against putting pressure on people for expressing their views.
This is Ayatollah Montazeri's second attack on the Iranian leadership in recent days. Last week, in his first public speech in six years, the ayatollah said most people in Iran were dissatisfied with their current rulers, and called for the issue to be put to the vote.