Rudy Giuliani revealed his need for "a few hundred thousand" and attacked Democratic 2020 hopeful Joe Biden in two voicemail messages accidentally left on an NBC reporter's phone.

The former New York City mayor is now U.S. President Donald Trump's personal lawyer and sits at the center of the impeachment scandal swirling at the White House gates.

Federal prosecutors in New York are investigating Giuliani's business dealings in Ukraine, CNN has reported, and he is searching for a new defense attorney.

NBC reporter Rich Shapiro revealed details of the messages on Saturday, describing the calls as "one of the most unfortunate of faux pas: what is known, in casual parlance, as a butt dial."

Call one: The Bidens

The first accidental message was delivered on the afternoon of September 28, the day after Shapiro had interviewed Giuliani for an article which carried allegations the president's lawyer may have committed crimes in his attempts to push Ukraine to investigate Biden.

The reporter colorfully recounts letting the call run to voicemail as a pink unicorn pinata was strung up for a family birthday party.

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Timeline: Trump, Biden and Ukraine

In The Spotlight: Hunter Biden

The three-minute message features a full-throated attack on former vice president Biden and his son Hunter, repeating allegations that have been widely debunked.

"You know how they get? Biden has been trading in on his public office since he was a senator," Giuliani says to an unidentified man, according to Shapiro.

"They don't want to investigate because he's protected, so we gotta force them to do it," Giuliani reportedly said at the end of the message, apparently referring to potential probes in Ukraine.

Call two: The Money

Shapiro had spoken to Giuliani on the evening of October 16 about his ties to an Iranian opposition group, but later received a second call from the former mayor.

The reporter was asleep, and the call went to voicemail.

"In the recording, the words tumbling out of Giuliani's mouth were not directed at the reporter. He was speaking to someone else, someone in the same room," Shapiro wrote.

Giuliani "can be heard discussing overseas dealings and lamenting the need for cash" in a conversation with another unidentified man, Shapiro writes.

The conversation reportedly touched on Bahrain, Turkey, a man named Robert, and Giuliani's need for money. 

"The problem is, we need some money," Giuliani says, adding a few seconds later, "We need a few hundred thousand."

A 'butt dial' history

The New York Times described the 75-year-old Giuliani as "an accomplished inadvertent caller" after Schapiro recounted his experience.

"Everyone has a good Rudy butt dial story," Josh Dawsey, a Washington Post reporter, tweeted.

Giuliani has not commented on the calls.

"I have yet to receive an intentional or unintentional call back," Schapiro told MSNBC.