The European Union and United States said they were studying Iran’s response to what the EU has called its “final” proposal to save a 2015 nuclear deal after Tehran called on Washington to show flexibility.

The US had already said on Monday that it was informing EU Foreign Policy chief Josep Borrell of its response to the text he submitted on August 8.

The possibility of a deal which might lead to the lifting of US sanctions on Iran’s oil output of 2.5 million barrels per day has already helped trigger a fall in prices on world markets, with US oil futures dropping nearly 3% to finish below USD 90 a barrel.