The Arabic-language Khaleej Online news website reported on Wednesday that the activists have recently held a meeting in the Hague to form the campaign.
The organizers of the campaign say bin Salman is accused of killing over 6,000 Yemeni children by launching a devastating war against the poor Arab state since 2015.
The international campaign underlines the necessity for rapid prosecution of bin Salman for his crimes which also include threatening and abduction of journalists and representatives of civil organizations.
The campaign has been formed at a time when the Saudi rulers, specially bin Salman, is facing accusations of the brutal murder of prominent journalist Jamal Khashoggi in Istanbul.
More than three weeks after the Saudi writer vanished, the details of his killing are still murky and the cause of his death is unknown. Officials in Riyadh have come up with shaky explanations for Khashoggi's demise; first stressing that he left the consulate alive, and then stating that he was killed accidentally in a fistfight, and finally alleging a "rogue operation" unbeknownst to the Saudi rulers.
Former CIA Director John Brennan said last week that he had "no doubt" that Saudi Crown Prince Mohammad bin Salman would have had prior knowledge of any plans to kill Jamal Khashoggi.
Speaking at a live event on Wednesday, Brennan joined the international chorus of condemnation of the murder, Al-Jazeera reported.
"Whether or not [Bin Salman] authorized the dismemberment, the horrific and brutal killing and torture of [Khashoggi] and the reported dismembering of his body, I don't know. But I have no doubt in my mind that MBS was fully aware of what was ultimately going to happen to Jamal Khashoggi and had approved it," he stressed.
Earlier, Brennan stated that the United States government is working with Saudi Arabia to “concoct a story” about the fate of Khashoggi.
Speaking to MSNBC on Wednesday, Brennan said bin Salman and the White House of President Donald Trump knew what happened to Khashoggi.
He also called on the CIA and other US intelligence agencies to hand in their evidence to Congress so that lawmakers could scrutinize the White House over its role in the alleged cover-up.