Washington (CNN) Rudy GIuliani said Monday that his work for President Donald Trump will not hurt his legacy as a once widely embraced mayor of New York.

"I am proud of what I'm doing," Giuliani said in an interview on CNN's "Cuomo Prime Time."

CNN's Chris Cuomo asked Giuliani in particular about the boos that the former mayor -- a rabid New York Yankees fan -- received at Yankee Stadium last week on his 74th birthday, suggesting his work for Trump contributed to the rude reception. Sporting a ritzy Yankees ring, Giuliani dismissed the inquiry.

"I have a clear conscience," Giuliani said. "I'm doing my job as a lawyer."

Giuliani, who gained worldwide acclaim for his leadership as New York City's mayor during the September 11 attacks, argued that his work for Trump served a broader purpose of protecting the office of the presidency.

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