New York (CNN) President Donald Trump's nominee to head the IRS owns a stake in two rental units at a Trump-branded hotel in Hawaii.

Charles Rettig was questioned by members of the Senate Finance Committee Thursday on topics ranging from his experience as a tax attorney to his management style.

He was also asked to demonstrate how he would remain independent from the Trump White House.

"That's important with any nominee, but it's especially relevant in Mr. Rettig's case, since he owns and rents out condos in a Trump-branded and managed property," Democratic ranking member Senator Ron Wyden said in his opening remarks.

Rettig owns a 50% stake in two rental units at the Waikiki Trump International Hotel and Tower. He noted the existence of those properties on his original financial disclosure form, but did not disclose that they were located at a Trump-branded hotel. He instead described them as "Honolulu, Hawai'i residential rental property," according to a memo from committee staff obtained by CNN.

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