Italy won’t take part in US President Donald Trump’s “Board of Peace” initiative, daily Corriere della Sera reported on Wednesday, citing concern that joining such a group led by a single country’s leader would violate Italy’s constitution.

Trump’s plan has so far drawn cautious reactions from Western allies, as diplomats say it could undermine the work of the United Nations.

On Thursday, Trump is due to preside over a ceremony celebrating the new group in Davos, Switzerland, the site of the World Economic Forum.

A source said that Italian Prime Minister Giorgia Meloni, a right-wing leader who has had warm relations with Trump, was unlikely to go to Davos, according to Reuters. The Italian government did not immediately respond to a request for comment.

The proposed board would be chaired for life by Trump and start by addressing the Gaza conflict before expanding to other wars. Member countries would be required to pay a $1 billion fee each to earn permanent membership.

According to Italy’s constitution, Italy may join international organisations that ensure “peace and justice among nations” only “on equal terms with other states”, a condition incompatible with US primacy on the new board, Corriere said.

The newspaper did not cite a source for its report.

Invitations to join the board have been addressed to some 60 nations, but just a few, including Hungary and Israel, have so far accepted without reservations. Adding to concern among Western allies, the Kremlin said this week that Russian President Vladimir Putin had also been invited.