What is the ruling on the state obliging (people) to pay a sum of money in dinars in addition to an amount in riyals for Hajj, and is the received money permissible, knowing that there is no other way to perform Hajj except through the state?

This transaction, where money is taken in dinars and then a portion is returned in another currency on the day of the Hajj trip, is not permissible. This is because it is considered a currency exchange (sarf), and delay is not allowed in currency exchange, as it leads to Riba al-Nasi'ah (interest due to delay), as evidenced by the hadiths in Bukhari and Muslim. The currencies and circulating banknotes of today have the same rulings as gold and silver. The responsible parties must modify this transaction by requesting the pilgrim to pay in the currency that will be returned to him (Saudi Riyal), or by returning the amount in the same currency that was received. If this is difficult and the responsible authorities do not respond to correct the transaction, then there is no blame on the pilgrim for engaging in it, and the sin falls upon the organizing entity.