Mike Bloomberg took a dig at Trump’s taxes while announcing his presidential bid

The billionaire former New York City mayor took a shot at fellow mogul Donald Trump when calling for higher taxes on the rich.

Former New York City mayor Mike Bloomberg confirmed he is running for the US presidency today, setting up a potential clash of the billionaires with a video that took an unsubtle dig at fellow mogul, president Donald Trump.

In an ad extolling Bloomberg’s business nous, philanthropy, and stewardship of New York City, his campaign called for an America “where the wealthy will pay more in taxes”—accompanied by a shot of Trump Tower.

Trump broke decades of precedent in 2016 by refusing to publish his tax returns, and has appealed to the Supreme Court to quash a subpoena issued as part of a criminal investigation by New York prosecutors. A Bloomberg campaign adviser has said the 77-year-old former mayor, who is worth an estimated $50 billion, will release his own returns at an undisclosed date.

Bloomberg, who made his money via his eponymous financial data company, hasn’t always been in favor of tax hikes on the wealthy—at least in New York City. In 2012, when candidates to replace him as mayor all proposed higher taxes for his peers, Bloomberg told reporters, “It is about as dumb a policy as I can think of.” He argued that rich people would move out of the city to avoid paying more.

The former mayor plans to make use of his riches in his bid to become Democratic presidential nominee. Last week, he stunned his opponents by booking airtime reportedly worth $34 million to run campaign ads. The figure dwarfs even the biggest war chests.

Senator Bernie Sanders decried the move as a “symptom of the problem” of the rich having too much power in America, and accused Bloomberg of “trying to buy an election.” Bloomberg spent at least $261 million in total on his three runs for the New York mayoralty, with each bid marking a record for campaign expenses in the city. In his last victory, in 2009, he put down $102 million, or $174 per vote—outspending his opponent by 14 to 1.

The former Republican is taking a highly unusual strategy in his late presidential run, eschewing early primary states like Iowa and New Hampshire—often seen as crucial in building a candidate’s momentum—and focusing on delegate-rich states like California and Texas.

Bloomberg is staking out a centrist, pragmatist stance, calling himself a “doer and a problem solver—not a talker.” But he will face heavy scrutiny over his business interests, history of crude remarks about women, and use of police tactics that discriminated against African Americans and Hispanics.