President Mahmoud Ahmadi-Nejad warned on Sunday that Iran would not retreat from its nuclear programme, while Tehran sought to underline its technological prowess by announcing that it had fired a rocket into the atmosphere.

“Iran has obtained the technology to produce nuclear fuel and Iran’s move is like a train that has no brakes . . . and no reverse gear,” Mr Ahmadi-Nejad said, according to Iran’s ISNA student news agency.