The son of the late Shah of Iran was surprised to hear the name of his grandfather being shouted openly on the streets of the Islamic Republic.

For the first time in decades, Reza Shah Pahlavi was once again on the lips and on the minds of at least some of its citizens.

“Reza Shah, rest in peace”, “What a mistake we made by taking part in the revolution” and “Bring back the Shah” were among the slogans cried out by protesters across the country.

Even in Qom and Mashhad, two of Iran’s two holiest cities, a few waved banners bearing the late king’s picture.

“It is like when clouds obscure the sun for some time - eventually light prevails,” Reza Pahlavi told the Telegraph last week.

The 57-year-old former crown prince left Iran as a teenager after his father Mohammed was overthrown in the 1979 Islamic Revolution. He now leads an opposition movement from his home in the US state of Maryland.