Tehran  - Iran's former chief nuclear negotiator Ali Larijani is to become the next speaker in the Iranian parliament, Tehran media reported Monday.

The two main conservative factions which in the elections last March won almost 70 per cent of the 290 seats have reportedly met on Sunday in Tehran and decided on Larijani to become the next parliament speaker, ISNA news agency reported.

Former speaker Gholam-Ali Hadad-Adel was reportedly rejected by the new members of parliament to continue in his position.

The new legislative period starts on Tuesday and the speaker will officially be elected after the inauguration ceremony. It remains unclear why the majority factions decided on the new speaker before the start of the new four-year term.

While Hadad-Adel is a close ally and considered a political guru of President Mahmoud Ahmadinejad, Larijani is a critic of the controversial Iranian president.

Larijani, who gained a big win in the elections as a candidate of the religious city of Qom, 130 kilometres south of Tehran, represents the so-called "conservative revisionists," a group that used to back the president but gradually grew apart from him and formed its own faction.

He resigned last October as chief nuclear negotiator after grave differences with Ahmadinejad over the country's nuclear policies and has since then been a critic of the president, especially regarding the president's economic policies which have caused high inflation.

If Larijani was also elected by the new MPs on Tuesday, then that would be the first signal of change in the legislative power indicating more parliamentary pressure on Ahmadinejad and his government.

The remaining 30 per cent in the parliament belongs to the reformist and independent wing which are not believed by observers to vote for Hadad-Adel, either.

Larijani is also expected to run again in the 2009 presidential elections and be one of the main challengers of Ahmadinjead. (dpa)