Hamza Bin Laden. File photo

Osama Bin Laden's son Hamza, chosen heir to the leadership of Al Qaeda, has been killed, US media reported Wednesday citing American officials.

NBC News said three US officials had confirmed they had information of Hamza Bin Laden's death, but gave no details of the place or date.

The New York Times subsequently cited two US officials saying they had confirmation that he was killed during the last two years in an operation that involved the United States.

Questioned by reporters in the Oval Office, President Donald Trump did not confirm or deny the NBC report.

"I don't want to comment on it," he said.

Both reports suggested that Bin Laden may have been killed well before the US State Department announced a $1 million bounty on his head in February 2019.

Osama Bin Laden. File photo/AFP

The 15th of Osama Bin Laden's 20 children and a son of his third wife, Hamza, thought to be about 30 years old, was "emerging as a leader in the Al-Qaeda franchise," the State Department said in announcing the reward.

Sometimes dubbed the "crown prince of jihad, he had put out audio and video messages calling for attacks on the United States and other countries, especially to avenge his father's killing by US forces in Pakistan in May 2011, the department said.

Documents seized in the raid on his father's house in Abbottabad suggested Hamza was being groomed as heir to the Al Qaeda leadership.

US forces also found a video of the wedding of Hamza to the daughter of another senior Al-Qaeda official that is believed to have taken place in Iran.

Hamza Bin Laden's whereabouts have never been pinpointed. He was believed to have been under house arrest in Iran but reports suggest he also may have resided in Afghanistan, Pakistan and Syria.

The group behind the deadly September 11, 2001 attacks on the United States, Al-Qaeda's prominence as a radical militant group has faded over the past decade in the shadow of the Daesh group.

But the proliferation of branches and associated militant groups in Afghanistan, Yemen, Syria and elsewhere has underscored its continuing potency.