The "fiduciary rule" that President Donald Trump wants to delay and review was "completely misintended," the White House's top economist told CNBC on Friday.

Trump is expected to direct the Labor Department on Friday to delay implementation for the next 90 days in order to review the Obama administration rule, which was designed to prevent conflicts of interest when financial advisors give retirement advice to people.

"They thought they were trying to protect investors in their retirement accounts. But by 'protecting investors,' they highly limited their choices," Trump aide Gary Cohn said on "Squawk on the Street." "I don't think you protect investors by limiting choices."

"When you're trying to encourage younger and younger people to invest for a longer period of time, you need to give them the proper choices that will allow them to accumulate wealth for a long period of time," said Cohn, director of the White House National Economic Council and former No. 2 executive at Goldman Sachs.

The president on Friday is also expected to sign an executive order directing the Treasury and other regulators to review parts of the Dodd-Frank banking reform law, including the Volcker Rule .

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