Osama bin Laden's son Hamza has issued chilling messages aimed at the Saudi royal family.

The 28-year-old, labelled the 'poster boy' for al Qaeda, is reportedly poised to lead the terror organisation in a bid to avenge his father's death.

The first video message from Hamza released a year ago hailed lone-wolf terror attacks and called for an uprising in the kingdom, according to AlMonitor.

The second accused Abdul-Aziz bin Rahman Al Saud - the first monarch and founder of Saudi Arabia - of being a British agent.

The son of Osama bin Laden (left) Hamza (right, in a graphic made by experts using age progression technology in a bid to picture him now) has issued chilling messages aimed at the Saudi royal family

Hamza bin Osama bin Laden pictured as a boy in 2001, displaying what the Taliban say is wreckage from a U.S. helicopter near Ghazni

Hamza claimed that the Saudis betrayed Islam by working with the 'crusaders' against the Ottoman caliphate.

Hamza has been a prominent figure in several propaganda videos for al Qaeda, even as a young boy.

He was filmed calling for terrorist attacks on London, Washington and Paris in an audio message released by the organization in 2015.

He has recorded four of theses types of messages in the last two years.

In January, Hamza was placed on a State Department terror watch list and named a 'specially designated global terrorist' - the same classification Osama had.

A former FBI agent who has read letters written by a 22-year-old Hamza, which are now declassified, said he seems motivated and prepared to avenge his father.

Ali Soufan was an agent who also served as the bureau's lead investigator of al Qaeda after 9/11. He said bin Laden's son was seen as the next possible leader of the terrorist organization when he was just a child, CBS News reported.

Principal among Hamza's messages is his desire for revenge.

Hamza has been a prominent figure in several propaganda videos for al Qaeda, even as a young boy

He was filmed calling for terrorist attacks on London, Washington and Paris in an audio message released by the organization in 2015

'He's basically saying, 'American people, we're coming and you're going to feel it. And we're going to take revenge for what you did to my father…Iraq…Afghanistan'…the whole thing was about vengeance,' Soufan said.

'He was a poster kid for the al Qaeda…and for members of al Qaeda, who were indoctrinated with these propaganda videos, he means a lot to them,' Soufan said.

Soufan said Hamza also uses the same terminology and sentences that his father once used.

Osama was killed in Abbottabad, Pakistan on May 2, 2011, by US Navy SEAL Team Six.

Following his death, dozens of letters written by him to his family and senior members of al Qaeda were released.

Senior intelligence officials claimed that some revealed he had been grooming his son to take over the terror group.

In one letter, Hamza's mother even implored her son to follow in his 'father's footsteps.'