A man armed with a pistol was arrested at the main gate of the tightly-guarded Pakistani Parliament on Monday just as Pakistan People's Party chairman Asif Ali Zardari arrived at the building ahead of the maiden session of the new National Assembly.

The man, whose identity was yet to be established, was overpowered by Zardari's private security guards and handed over to police.

It was not clear how the man had managed to enter the Parliament complex with a weapon despite the unprecedented security arrangements put in place for the session during which parliamentarians will be administered the oath by outgoing Speaker Chaudhry Amir Hussain.

Unlike other political leaders, Zardari did not interact with journalists who had gathered near the Parliament and drove straight up to the gate of the building in his armoured vehicle.

Zardari became co-chairman of the PPP after his wife, former premier Benazir Bhutto [Images], was assassinated by a suicide attacker in a pre-poll party rally in December 2007.

Security agencies and police had put in place stringent security arrangements at the heavily barricaded Parliament building and surrounding areas.

Several key roads in the heart of Islamabad were blocked and entry to the area around the Parliament was restricted.