An ideological split at International Atomic Energy Agency is slowing the search for a new chief at a time the organisation tasked with keeping nuclear arms away from rogue states needs a firm hand at the rudder.

The longer the delay, the greater the fear that Iran, and possibly Syria, could forge ahead with allegedly illicit nuclear activities with more impunity.

For months, the IAEA's hands have been tied in its probes of the two nations' nuclear programmes as internal bickering and the agency's weak mandate prevent it from taking effective action The hunt is on for a leader who can help unite the fractious 35-nation board for joint decisions on crucial nonproliferation issues.

But the same North-South divisions that have hobbled the IAEA's investigation of Iran and Syria are encumbering the search for a successor to Mohamed ElBaradei, who steps down as director general in November. The developed world believes tough action is needed to block rogue nations from acquiring nuclear weapons; emerging economies argue that countries like Iran and Syria have a right to develop nuclear programmes to help them catch up with the West.