°®Âþµº

The chief of Iran's nuclear agency says the country's effort to acquire uranium has resulted in a stockpile of as much as 950 tonnes.

Ali Akbar Salehi, head of Iran's Atomic Energy Organisation, tells state TV on Wednesday that Iran has imported some 400 tons of the stuff since the 2015 landmark nuclear deal with Western powers, bringing its stockpile to between 900 and 950 tonnes - up from 500.

Salehi says that's enough for Iran to run its longtime goal of 190,000 centrifuge machines for enriching uranium in the future.

The nuclear accord limits Iran's uranium enrichment to 3.67 percent, enough to use in a nuclear power plant but far lower than the 90 percent needed for an atomic weapon.

However, since the US pulled out of the deal in May, Iran has vowed to boost enrichment capacity to put pressure on the remaining signatories to live up to the agreement.

In a bid to save the accord, the EU and European parties to the deal - Britain, France and Germany - presented a series of economic "guarantees" to Iran this month, but these were judged "insufficient" by Tehran.

Negotiations are continuing, and foreign ministry spokesman Bahram Ghasemi said on Monday they could last several "weeks", according to state television.

In June, in a bid to mount pressure on the Europeans, Iran announced a plan to increase its uranium enrichment capacity with new centrifuges in the event that the agreement collapses, while still denying any desire to build a nuclear weapon.