President Biden told business leaders Wednesday that former President Donald Trump is an “existential threat” during a three-stop fundraising tour of New York City that was beset by anti-Israel protesters who blocked Fifth Avenue outside the Metropolitan Museum of Art.

“There is one existential threat: it’s Donald Trump,” the 81-year-old president said at his first stop of the day — an environment-focused afternoon gathering at the Upper West Side home of Larry Linden, the former managing partner of Goldman Sachs.

“He’ll try to undo everything we’ve done. Make no mistake …We can’t let that happen,” Biden told the approximately 17 invited guests, before adding, “There is only one existential threat we face in the world: and that’s the environment.”

Businessmen whose environmental projects align with Biden’s program of subsidies and incentives were expected to attend, including Earthrise Energy director Reuben Munger and David Elenowitz of Zero Carbon Partners, Bloomberg reported.

Bain Capital co-chairman Josh Bekenstein, real estate magnate Dan Tishman and hedge fund founder Mark Gallogly also were expected to attend.

The second fundraiser was held at the decadent Mandarin Oriental Hotel near Columbus Circle and was hosted by Dr. Ramon Tallaj, chairman of the nonprofit SOMOS Community Care and a member of Mayor Eric Adams’s COVID-19 recovery task force.

JPMorgan managing director Nikul Patel was expected to attend, as was investor Michael Sonnenfeldt, chairman and founder of Tiger21, an organization that describes itself as “the premier peer-to-peer learning network for high-net-worth first generation wealth creators in North America and Europe.”

Biden was expected to attend the third fundraiser in one of the high-rise apartments lining Fifth Avenue.

Demonstrators camped out in the thoroughfare during rush hour. There were not immediate reports on a number of arrests.

Biden made the fundraising blitz as he seeks to maintain his large cash advantage over presumptive Republican presidential nominee Donald Trump, who is leading in most national and swing-state polls despite facing up to four criminal trials before the November election.

This is a developing story; check back for more updates