There were also signs that the leadership could be preparing to announce an increase in the level to which it enriches uranium. The Majlis called on the government to start building ships “not reliant on fossil fuels” – a clear reference to an announcement by the Iranian navy last month that it was planning to build nuclear-powered submarines.

Such vessels can use anything from the 20%-enriched uranium which Iran is currently making, to 90%, weapons-grade fuel. There were unconfirmed reports from Tehran on Monday that President Mahmoud Ahmadinejad was preparing to announce a new target for enrichment at some point between those two levels.

Such a move would be seen as provocative by much of the international community, as it would bring Iran far closer to the capacity to make the fissile core for a nuclear weapon