The board, chaired by Trump, was originally envisioned as a small group of world leaders overseeing the Gaza ceasefire plan.
The Trump administration's ambitions have appeared to balloon into a more sprawling concept, with Trump extending invitations to dozens of nations and hinting it will soon broker global conflicts.
Netanyahu's office had previously said the executive committee - which includes Turkey, a key regional rival - wasn't co-ordinated with the Israeli government and "is contrary to its policy", without clarifying its objections.
Israel's far-right finance minister, Bezalel Smotrich, has criticised the board and called for Israel to take unilateral responsibility for Gaza's future.
Others who have joined the board are the UAE, Morocco, Vietnam, Belarus, Hungary, Kazakhstan and Argentina.
Others, including the UK, Russia and the executive arm of the European Union, say they have received invitations but have not yet responded.
It came as Trump travelled to the World Economic Forum meeting in Davos, Switzerland, where he is expected to provide more details about the board.
When asked by a reporter if the board should replace the UN, Trump said, "It might."
He said the world body "hasn't been very helpful" and "has never lived up to its potential" but also said the UN should continue "because the potential is so great".
That has created controversy, with some concerned Trump is trying to replace the UN, including French Foreign Minister Jean-Noel Barrot.
"Yes to implementing the peace plan presented by the president of the United States, which we wholeheartedly support, but no to creating an organisation as it has been presented, which would replace the United Nations," Barrot said.
Told that French President Emmanuel Macron was unlikely to join, Trump said, "Well, nobody wants him because he's going to be out of office very soon".
A day later, Trump called Macron "a friend of mine" but reiterated the French leader is "not going to be there very much longer".
The executive board's members include US Secretary of State Marco Rubio, Trump envoy Steve Witkoff, Trump's son-in-law Jared Kushner, former British prime minister Tony Blair, Apollo Global Management chief executive Marc Rowan, World Bank president Ajay Banga, and Trump's deputy national security adviser Robert Gabriel.
The White House also announced the members of another board, the Gaza Executive Board, which, according to the ceasefire, will be in charge of implementing the tough second phase of the agreement.
That includes deploying an international security force, disarming Hamas and rebuilding the war-devastated territory.
Nickolay Mladenov, a former Bulgarian politician and UN Mideast envoy, is to serve as the Gaza executive board's representative overseeing day-to-day matters.
Additional members include: Witkoff, Kushner, Blair, Rowan, Turkish Foreign Minister Hakan Fidan; Qatari diplomat Ali Al-Thawadi; Hassan Rashad, director of Egypt's General Intelligence Agency; Emirati minister Reem Al-Hashimy; Israeli businessman Yakir Gabay; and Sigrid Kaag, the Netherlands' former deputy prime minister and a Mideast expert.
The board also will supervise a newly appointed committee of Palestinian technocrats who will be running Gaza's day-to-day affairs.
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