Iran has begun injecting uranium gas into advanced centrifuges in violation of its nuclear deal with world powers, a spokesman has announced.

Behrouz Kamalvandi of the Atomic Energy Organisation of Iran warned Europe had little time left to save the 2015 deal.

Donald Trump, the US president, withdrew America from the nuclear accord over a year ago before imposing crippling trade sanctions on Iran.

“Our stockpile is quickly increasing,” Mr Kamalvandi warned in a news conference. “We hope they will come to their senses.”

Iran has already breached the stockpile and enrichment level limits set by the deal, while stressing it could quickly revert back to the terms of the accord, if Europe delivers the sanctions relief promised in return for curbing Tehran’s nuclear programme.

Tensions high as Trump approves new Iran sanctions: In pictures Show all 17 1 /17 Tensions high as Trump approves new Iran sanctions: In pictures Tensions high as Trump approves new Iran sanctions: In pictures Iran claims that in this picture released by Iran state TV, their surface-to-air missile is seen as it shoots down a US surveillance drone EPA Tensions high as Trump approves new Iran sanctions: In pictures This photo shows US RQ-4A Global Hawk unmanned surveillance drone. A drone of this model was shot down by Iran on Thursday 21 June AFP/Getty Tensions high as Trump approves new Iran sanctions: In pictures An oil tanker is on fire after it was subject to a suspected attacked at the Gulf of Oman on June 13. The US has blamed Iran for the attack Reuters Tensions high as Trump approves new Iran sanctions: In pictures Iran claims that in this picture released by Iran state TV, debris from the downed US drone is seen after it was recovered from Iranian waters AFP/Getty Tensions high as Trump approves new Iran sanctions: In pictures Smoke billows from an oil tanker after it was subject to a suspected attacked at the Gulf of Oman on June 13 Reuters Tensions high as Trump approves new Iran sanctions: In pictures US President Trump holds up a signed executive order to increase sanctions on Iran on 24 June AP Tensions high as Trump approves new Iran sanctions: In pictures Iranian President Rouhani stated in a televised address that the White House is "afflicted by mental retardation" following the increase in sanctions on 25 June EPA Tensions high as Trump approves new Iran sanctions: In pictures An Iranian navy boat tackles the fire on the Norwegian owned Front Altair oil tanker after it was hit in a suspected attack AFP/Getty Tensions high as Trump approves new Iran sanctions: In pictures Iran claims that in this picture released by Iran state TV, debris from the downed US drone is seen after it was recovered from Iranian waters AFP/Getty Tensions high as Trump approves new Iran sanctions: In pictures Smoke billows from an oil tanker after it was subject to a suspected attacked at the Gulf of Oman on June 13 Reuters Tensions high as Trump approves new Iran sanctions: In pictures A screenshot from a video released by the US Department of Defense that the US claims to show Iranian removing an unexploded limpet mine form the hull of the Japan-owned ship that was attacked in the Gulf of Oman on June 13 Getty Tensions high as Trump approves new Iran sanctions: In pictures An item reportedly found on the Japan-owned oil tanker that was attacked on June 13 in the Gulf of Oman AFP/Getty Tensions high as Trump approves new Iran sanctions: In pictures A handout photograph from the US Department of Defense shows a composite material that the US claim was left behind on the hull of the Japan-owned oil tanker following the removal of an unexploded limpet mine Getty Tensions high as Trump approves new Iran sanctions: In pictures A view from the cabin of an Iranian navy boat as it tackles the fire on the Norwegian owned Front Altair oil tanker after it was hit in a suspected attack EPA Tensions high as Trump approves new Iran sanctions: In pictures Release by US government A picture released by U.S. Central Command shows damage to the hull of the oil tanker Kokuka Courageous. The picture suggests that the ship is 'likely' to have been hit by a mine as the US Secretary of State Mike Pompeo moves to blame Iran for the suspected attack Reuters Tensions high as Trump approves new Iran sanctions: In pictures Smoke billows from an oil tanker after it was subject to a suspected attacked at the Gulf of Oman on June 13 Reuters Tensions high as Trump approves new Iran sanctions: In pictures Release by US government A picture released by U.S. Central Command shows damage to the hull of the oil tanker Kokuka Courageous. The pictures suggests that the ship is 'likely' to have been hit by a mine as the US Secretary of State Mike Pompeo moves to blame Iran for the suspected attack EPA

Mr Kamalvandi said Iran had the ability to go beyond 20 per cent enrichment of uranium.

Analysts have warned 20 per cent is a short technical step away from 90 per cent enrichment, which is weapons-grade level.

While Mr Kamalvandi stressed “the Islamic Republic is not after the bomb,” he warned Iran was running out of ways to stay in the accord.

“If Europeans want to make any decision, they should do it soon,” he said.

Mr Kamalvandi warned several times in his comments that Iran was rapidly approaching a point that would mean a full withdrawal from the deal.

“Our stockpile is quickly increasing, we hope they will come to their senses,” he said.

However, he stressed that Iran would allow UN inspectors to continue to monitor sites in the country. He made the announcement, broadcast on live TV, from a podium with advanced centrifuges standing in the foreground.

A top official from the UN’s International Atomic Energy Agency was expected to meet with Iranian officials in Tehran on Sunday.

Donald Trump and Hassan Rouhani suggest they could meet to resolve US-Iran crisis

Tensions between Iran and the US have risen in recent months, during which mysterious attacks on oil tankers near the Strait of Hormuz have taken place and Iran has shot down a US military surveillance drone.

On Saturday, satellite images showed a once-detained Iranian oil tanker pursued by the US appears to be off the coast of Syria, where Tehran reportedly promised the vessel would not go when authorities in Gibraltar agreed to release it several weeks ago.