Investors bought less than 60 per cent of the 5 per cent stake in Bank Mellat offered for sale on 18 February.

Under capital markets rules in Iran, the stock exchange has to review any IPO that fails to sell 60 per cent of the stake put on sale.

If fewer than half of the available shares had been bought, the exchange would have had to cancel the exercise.

The senior managers of the exchange have to inform the market before it opens on 21 February whether they have cancelled the IPO.

If it is cancelled, Bank Mellat will need to reissue the shares at a cheaper price than the IR1,050 ($0.11) offered on 18 February.