Prince Trurki al-Faisal of Saudi Arabia says that if the West strikes a nuclear deal with Iran, it is likely that many other countries will demand the same allowances.
During an interview with the BBC, he warned that Saudi Arabia was among the nations that would seek the same rights, and that a situation where Iran could continue its enrichment programme would lead to the development of atomic weapons elsewhere.
"I've always said whatever comes out of these talks, we will want the same," he said. "So if Iran has the ability to enrich uranium to whatever level, it's not just Saudi Arabia that's going to ask for that.
"The whole world will be an open door to go that route without any inhibition, and that's my main objection to this P5+1 [the six world powers] process.”
Talks are currently taking place between six world powers, with the 31 March deadline approaching quickly. Sanctions have been placed on Iran until it curbs its nuclear enrichment programme, but the extent to which the nuclear activity should be limited is a point of contention.
Earlier this month, US President Barack Obama proposed a ten-year freeze on nuclear enrichment in return for a lifting of sanctions, arguing that this was a better option than taking military action on the country.
But he has faced intense pressure from Congress not to agree to a deal that would allow Iran to continue building a weapon, while Israeli Prime Minister Benjamin Netanyahu has argued that a nuclear-armed Iran would pose an existential threat to the Jewish state.
Iran has consistently denied that it is trying to build an atomic bomb, saying instead that its enrichment is entirely for civilian purposes.