Reza Pahlavi was seven when he grasped something was different about him.

Riding in a horse-drawn carriage through the streets of Tehran after his father’s coronation in 1967, he noticed that the crowds were not only cheering his parents’ carriage, “I realised they were cheering me,” he recalls. “That was the moment it clicked, that I’m special, or important. It triggered something in my head.

“There was the people’s enthusiasm, love and affection, but at the same time an expectation of what it means to be a crown prince. [And it made me think] what does it entail in terms of all the dedication, sacrifice, responsibility and limitations that you have to accept because of that elevated expectation?”

The adoration did not last. In 1979, Pahlavi was driven into exile by a popular revolution sparked by his father’s misrule. The uprising ended with the establishment of the Islamic Republic of Iran.

Yet Pahlavi, 64, still speaks with the self-confidence of one raised to rule. And he now predicts a revolution similar to the one that overthrew his father.

‘A window of opportunity’

Economically strangled at home, militarily bloodied abroad and ideologically moribund, the Islamic Republic is rapidly losing authority even among long-time supporters, he argues. Western governments must seize this moment to assist Iranians to usher in a secular democracy via civil disobedience.

“There is a critical window of opportunity to change history. It may only be open for a few months,” he says. “Now is the time to act. Iran is in a revolutionary, or at the very least, a pre-revolutionary fervour. It’s escalating every day. All the chants you hear on the streets, all the protests, all the demonstrations that specifically call for an end to this regime, death to the dictator, death to the Islamic Republic.

“It is in plain view. Especially on the 46th anniversary of the revolution [which saw official celebrations marred by anti-regime protests this month]. It’s not just isolated to one pocket of resistance here and there,” he tells me during a visit to the Telegraph office to record a special edition of the Battle Lines foreign policy podcast..

A tall man who bears a striking resemblance to his father, the shah Mohammad Reza Pahlavi, who ruled Iran from 1941 until the 1979 revolution, Pahlavi has been on a frenetic diplomatic tour of Europe, which included a visit to last week’s Munich Security Conference.

Accompanied by an entourage of guards and advisers, he has for the past fortnight busily worked the corridors of foreign capitals to lobby Western governments to prepare for the collapse of the Islamic Republic. It is not always an easy sell.