Concerns also emerged last year about the accuracy of nuclear reactor monitoring instruments during testing.

BBC: HMS Audacious: MoD announces ?1.2bn submarine contract

But the IAEA reported that Iran still seemed to be in the testing phase of fueling the reactor.

WSJ: Iran Is Ramping Up Nuclear-Fuel Output

The Sunshine to Petrol project is testing a prototype device called the Counter Rotating Ring Receiver Reactor Recuperator (called CR5 for short) which turns CO2 into carbon monoxide which could then form part of a liquid fuel.

CNN: Turning carbon dioxide into fuel