A leading Islamist candidate for the Egyptian presidency was attacked by armed men overnight and was in an intensive care unit in hospital suffering from brain concussion, aides said on Friday.

Abdel Moneim Abol Fotoh, 60, was on his way home from a campaign event in the city of Munufeya when three armed men wearing masks and carrying machineguns stopped him.

"They beat him on the head repeatedly, took the car and ran," said campaign team member Ahmed Osama.

"He is now in the intensive care unit and conscious," said Osama.

The attack occurred two weeks before candidates register to run in the presidential election that Egypt is holding under plans by the ruling military council to hand over power to a new head of state at the end of June.

Abol Fotoh was expelled from the Muslim Brotherhood, which emerged as the biggest single party in a parliamentary election, when he defied its decision not to put up a presidential candidate.

Sheikh Yousef al-Qaradawi, one of the most widely respected Sunni Muslim clerics in the Arab world, has described Abol Fotoh as the "leading candidate" in a field including former Arab League Secretary General Amr Moussa, a liberal and former foreign minister.

The Muslim Brotherhood's decision not to field its own presidential candidate is part of an effort to ease concerns at home and abroad about Islamist domination of Egypt after an uprising toppled Hosni Mubarak from 30 years of power last February.

The military council has ruled Egypt since then.