Trump is due in the French capital along with around 70 other world leaders for a ceremony on the Champs-Elysees on Sunday to mark the 100th anniversary
of the end of World War I.
Dozens of leaders, including Russian President Vladimir Putin, Turkey's Recep Tayyip Erdogan and Germany's Angela Merkel, are then expected to attend the opening of the inaugural Paris Peace Forum, which Macron will host.
Ending uncertainty about whether the US leader would participate, chief organiser Justin Vaisse confirmed to AFP on Thursday that Trump would not attend.
Earlier this week, Vaisse had played down the importance of his presence — while explaining why Trump might not have found the agenda to his liking.
“The aim of the forum is to show that there are lots of forces in the international system — states, NGOs, Foundations, intellectuals, companies — who believe we need a world of rules, an open world and a multilateral world,” he said.
“This world needs to meet up and defend itself,” he said. “It doesn't matter if those who don't believe in multilateralism aren't there.”
Macron has been an outspoken critic of Trump's “America First” policies and his decisions to pull out of international agreements such as the Paris climate accord, the Iran nuclear deal and most recently a nuclear arms treaty.
While the two leaders struck up a warm relationship initially, particularly during Trump's first visit to Paris as president in July 2017, their ties have
cooled recently amid a growing list of disagreements, diplomats say.
Macron has used the WWI commemorations to issue a series of warnings about the rise of nationalism across the world — embodied by Trump — and has
likened it to “leprosy”.
The Paris Peace Forum, which will run until Tuesday, is part of what he sees as a “fightback” against nationalist forces which risk destabilising the international system, Vaisse said.
Macron conceived the forum as an annual gathering for political leaders and civil society groups to discuss democracy — along the same lines as the Davos
meeting in Switzerland, which is devoted to economics and business.