Bloomberg endorsed Biden’s reelection Thursday in a statement to The Washington Post, in response to a request for comment on the donations.

“I stood with Joe Biden in 2020, and I am proud to do so again,” Bloomberg said.

These are the first public donations in the 2024 presidential race from the wealthy Republican-turned-Democrat, who has become a reliable source of major funding for Democrats in recent campaign cycles. The transfers were described by multiple people familiar with them who spoke on the condition of anonymity because they were not authorized to speak publicly.

Bloomberg, 82, who served three terms as the mayor of New York City, is the 15th wealthiest person in the world, according to Forbes magazine, with about $106 billion in assets, mostly through his privately-held financial services company, Bloomberg LP.

Bloomberg spent about $1 billion on his own 2020 bid for the Democratic nomination, including $18 million that he later transferred to the Democratic Party to help Biden’s campaign after Bloomberg left the race. The former mayor later announced a separate $100 million independent ad campaign to help Biden in Florida, which Trump won by more than three percentage points.

“Michael Bloomberg was a strong supporter of President Biden in 2020 and, now, again in 2024, and we are very grateful for his support,” FF PAC President Chauncey McLean said in a statement Thursday. “Voters respond when they hear the story about President Biden looking out for them while Donald Trump just looks out for himself. Because of Michael Bloomberg’s support, we’ll be more successful in making sure people understand the choice in this election.”

Bloomberg was the largest single donor to FF PAC during the latest filing period, joining other major donors like the International Union of Painters and Allied Trades, Laborers International Union, SEIU, United Association and the Transport Workers Union, according to a person familiar with donations.

The group has announced plans for a $250 million digital and television ad campaign starting after the August Democratic nominating convention in Chicago. Additional summer advertising before then is expected to be announced in the coming weeks.

A partner group, Future Forward USA Action, which does not disclose its donors, spent $22 million on advertising to educate people about Biden’s record last year, according to the tracking firm AdImpact. Future Forward USA Action has also partnered with Climate Power to spend an additional $11 million in similar ads so far, including spots that are now running in swing states.

Biden offered effusive praise to Bloomberg during a May 3 White House ceremony that awarded Bloomberg the Presidential Medal of Freedom, the nation’s highest civilian honor.

“He’s changed us. He’s challenged us, as well, to solve the toughest challenges from gun violence to climate change,” Biden said. “Michael, thank you, Mr. Mayor. Thank you for a career of service.”