Western governments risk creating a new generation of Islamist extremists if they continue to support repressive regimes in the Middle East, the former UN nuclear weapons chief Mohamed ElBaradei has told the Guardian.

In his first English-language interview since returning to Cairo in February, the highly respected Nobel peace prize-winner said the strategy of supporting authoritarian rulers in an effort to combat the threat of Islamic extremism had been a failure, with potentially disastrous consequences.

ElBaradei, who has emerged as a potential challenger to the three-decade rule of Egypt's president, Hosni Mubarak, said: "There is a need for re-evaluation ... The idea that the only alternative to authoritarian regimes is [Osama] Bin Laden and co is a fake one, yet continuation of current policies will make that prophecy come true.