Mr Nateq-Nouri, a prominent conservative, scored a comfortable victory by securing 165 votes, compared with 84 for radical left-wing opponent, Majid Ansari.

The BBC Middle East correspondent, Jim Muir, says his victory is no surprise since Mr Nateq-Nouri won re-election as speaker unopposed last year - despite his massive defeat in the presidential elections by the hugely-popular Mr Khatami.

Power struggle

However, he says Mr Nateq-Nouri's re-election highlights the divide between between moderate reformists and radical leftists among the Iranian president's supporters in the parliament.

Reformist president, Mohammad Khatami, worried about conservatives

Our correspondent says the next focus for the constitutional struggle between hard-line conservatives and reformers is likely to be the nation-wide elections for the Council of Experts in September.

The council, made up of 83 senior clerics, is the only body with the power to appoint or dismiss the Islamic republic's Supreme Leader, currently Ayatollah Ali Khamene'i.