Donald Trump. Getty Images Sen. Bob Casey of Pennsylvania wasted little time in taking aim at President Donald Trump's tweet attacking Nordstrom on Wednesday morning, referring it to the Office of Government Ethics for review.

"CC: @OfficeGovEthics," Casey wrote, quoting Trump's tweet from minutes earlier saying the department store was treating his daughter Ivanka "unfairly" by dropping her brand from its stores last week.

"My daughter Ivanka has been treated so unfairly by Nordstrom," Trump wrote. "She is a great person — always pushing me to do the right thing! Terrible!"

Ivanka — whose husband, Jared Kushner, is a senior White House adviser — did not take a position in her father's administration. However, she stepped down from her roles with the Trump Organization and her fashion brands to help clear up any potential conflicts of interest or ethical issues.

Nordstrom told Business Insider the brand was cut from its offerings based on poor performance.

Questions regarding Trump's own conflicts of interest have swirled in the months since he won the presidency. He announced in mid-January his plan to separate himself from his businesses and put his two adult sons, Donald Jr. and Eric, in charge, in addition to a senior Trump Organization employee.

However, many ethics experts said they felt Trump did not go far enough in resolving the potential conflicts. Since then, ProPublica revealed a document that showed Trump had placed his business assets into a revocable trust run by the two sons. As CNN wrote Wednesday, the White House has yet to make public information about how the trust would work.