Spain's Repsol has announced it is pulling out of a contract it had won with Royal Dutch Shell to develop part of the South Pars gas field in Iran, Reuters has reported. The firm was given an ultimatum by Iran to finalise its initial decision in May or withdraw. A spokesman for Shell declined to confirm whether the company will remain to develop phases 13 and 14 of the South Pars project, but noted that Shell will comply with any international trade restrictions which are placed on Iran.