Michael Bloomberg, the billionaire and former mayor of New York, will explore a run for president, according to an email to employees from management of the financial data and publishing empire that bears his name.

Bloomberg, 77 years old, had said earlier this year he wouldn't run for president but his political adviser told the Associated Press that Bloomberg was concerned the current array of candidates for the Democratic nomination aren't "well-positioned" to defeat President Donald Trump.

Billionaires who are curious about how much they would pay in taxes under a President Warren administration can plug in their net worth and find out just how much they'd pay in taxes under her ultra-millionaire tax.

And in a jab to some of the billionaires who this week have publicly criticized Warren's plan, the website specifically has links saying, "If you're Michael Bloomberg, click here," "And if you're Bill Gates, you can click here," "And if you're Leon Cooperman, just click here."

Cooperman is a hedge-fund manager and CEO of the New York firm Omega Advisors.

Former New York Mayor Bloomberg, who runs the financial-services firm Bloomberg LP, is inching closer to becoming Warren's political rival, with multiple reports saying he's expected to enter the race for the Democratic Party nomination.

Here is a transcript of the email sent to Bloomberg employees Friday morning:

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"As you likely heard, Mike has decided to explore a campaign for president of the United States. 

No final decision has been made, but of course this is nothing new to the company. When Mike ran for City Hall, we kept the business moving forward, and when Mike became Mayor, the company continued to grow and innovate.

If Mike steps away again, we have an expanded Management Committee well equipped to continue running the day-to-day operations of the company.We are well on track for our 38th consecutive year of revenue growth because of your efforts. Thank you for everything you have done.

Let's close out another strong year."

Sen. Elizabeth Warren (D.-Mass.), who has taken a front-runner position for the Democratic nomination, hasn't backed down from her plan to tax the wealthy at a higher rate, going as far to add a billionaire tax calculator to her campaign website.

According to Forbes, Bloomberg's net worth is $52.4 billion, giving him a Warren tax bill of $3.08 billion.

"This amount, which you likely won't even feel, will help us invest in education from birth through college and help finance health care for everyone," Warren's campaign website said of Bloomberg's potential tax bill. 

Leon Cooperman, who also has been battling Warren, said Friday he will support fellow billionaire Bloomberg for president, according to CNBC.