U.S. President Donald Trump, a frequent critic of the United Nations, will seek to galvanize global support for reforming the world body at an event he will host at UN headquarters in New York on September 18, media reported on September 1.

Countries will be invited to attend Trump's function if they sign onto a declaration backing efforts by UN Secretary-General Antonio Guterres "to initiate effective, meaningful reform" that eliminates duplication among the UN's many agencies, according to Reuters and AFP, which said they have seen the document.

Trump has complained that the U.S. share of the UN's budget is too high and has proposed slashing funding. He hasdescribed the UN as an "underperformer" and recreational "club."

But Trump has also said U.S. funding of about a quarter of the UN's $12.7 billion annual budget is "peanuts," given the UN's "huge potential" and mission to address a long list of world problems.

Diplomats said speakers at the planned event, which will come a day before Trump addresses the General Assembly, include Trump, Guterres, and U.S. Ambassador to the UN Nikki Haley.

Based on reporting by AFP and Reuters