Saudi Arabia has stripped Osama bin Laden's son Hamza of his citizenship, one day after the United States offered a $1 million reward for information that could lead to his capture.

The son of the late al-Qaeda leader, who was killed in a U.S. military raid in Pakistan in 2011, has reportedly become an increasingly prominent figure in the terror network.

Saudi Arabia's interior ministry announced that they had revoked his citizenship via a royal decree in November, however it is not known why it was only made public today.

Hamza, who is thought to be about 30 years old has released audio and video messages calling for 'lone wolf' attacks against the U.S. and its allies.

The large bounty, part of the U.S. State Department's 'rewards for justice' programme, is due to renewed fear that another al-Qaeda terror attack on the west is imminent.

Hamza bin Laden pictured at his wedding, where he repotedly married the daughter of Mohammed Atta, the 'lead hijacker and a mastermind' of the 9/11 attacks. Saudi Arabia publicly announced today that they have stripped Hamza of his citizenship

The United States is offering a $1 million reward for information on Hamza bin Laden, seen here in a video grab by the CIA

'Hamza bin Laden is the son of deceased former AQ leader Osama bin Laden and is emerging as a leader in the AQ franchise,' a State Department statement said, referring to al-Qaeda.

The junior bin Laden was named a 'specially designated global terrorist' in January 2017 and has threatened revenge for his father's 2011 killing by U.S. forces, the department said in a statement.

Osama bin Laden was killed in a covert operation carried out in Abbottabad, Pakistan at a compound where the al-Qaeda leader was holed up.

In addition, Hamza allegedly married the daughter of Mohammed Atta, the 'lead hijacker and a mastermind' of the 9/11 attacks.

Bin Laden and al-Qaeda claimed responsibility for the 9/11 terrorist attacks in the U.S. and other notorious actions.

Osama Bin Laden and Al-Qaida claimed responsibility for the 9/11 terrorist attacks in the U.S. and other notorious actions

Nearly 3,000 people were killed that day, including citizens of roughly 77 countries.

US intelligence agencies increasingly see the younger bin Laden as a successor to his father for the mantle of global jihad, especially as the even more extreme Islamic State group is down to its last sliver of land in Syria.

In 2015, bin Laden released an audio message urging jihadists in Syria to unite, claiming that the fight in the war-torn country paves the way to 'liberating Palestine.'

And in a message a year later, following in the footsteps of his father, he urged the overthrow of the leadership in their native Saudi Arabia.

Osama bin Laden was killed in a covert operation carried out in Abbottabad, Pakistan in May 2011, and his son has reported threatened retaliation against the U.S. for his death

Osama bin Laden's three surviving wives and his children were quietly allowed to return to Saudi Arabia after his killing.

But Hamza bin Laden's whereabouts have been a matter of dispute. He is believed to have spent years along with his mother in Iran, despite Al-Qaeda's strident denunciations of the Shiite branch of Islam that dominates the country.

Observers say that the clerical regime in Tehran kept him under house arrest as a way to maintain pressure on rival Saudi Arabia as well as on Al-Qaeda, dissuading the Sunni militants from attacking Iran.

One of Hamza bin Laden's half-brothers told The Guardian last year that Hamza's whereabouts were unknown but that he may be in Afghanistan.