NEW YORK — Former U.S. President George W. Bush will keynote a summit next month on fighting global extremism, organizers announced Monday.

The nonprofit Concordia Summit Group said Bush will be joined by other former world leaders, security experts and heads of global corporations at the Sept. 20 meeting which aims “to strengthen the relationship between the public and private sectors to more effectively combat extremism on a global scale.”

Bush, who was president on 9/11, declined an invitation from President Barack Obama to attend a somber remembrance on May 5 at the World Trade Center site to mark the killing by U.S. forces of Osama bin Laden.

The former president will be near the site when he attends the Sept. 20 summit at the Ritz-Carlton Battery Park Hotel, which overlooks the Statue of Liberty.

The summit is taking place on the eve of the annual ministerial meeting of the U.N. General Assembly, which Obama is scheduled to address on Sept. 21.

Concordia said other participants at the summit will include former Colombian President Alvaro Uribe and 9/11 commission chair Thomas Kean. It also will include former U.S. ambassador to the United Nations John Negroponte and former U.S. undersecretary of state Paula Dobriansky, who both served under Bush.

The Concordia Summit Group was founded in February by Matthew Swift and Nicholas Logothetis, who both had long careers with Rupert Murdoch’s News Corporation.

Its advisory board includes Bush’s former homeland security adviser, Frances Townsend, former Latvian president Vaira Vike-Freiberga and former Polish president Aleksander Kwasniewski.