Sean Spicer says: "She's been counseled, and that's all we're going to say."
Conway spoke on Fox News Thursday morning from the White House briefing room. She encouraged people to "go buy Ivanka's stuff."
She made the comments a day after Trump attacked Nordstrom on Twitter for dropping his daughter's fashion line.
While Trump himself is not subject to the standards of ethical conduct for federal employees, Conway is. Among the rules: An employee shall not use his or her office "for the endorsement of any product, service or enterprise."
ORIGINAL REPORT: As Trump's criticism intensifies, Nordstrom sticks to its guns
House Oversight Chairman Jason Chaffetz said Conway's comment was "wrong, wrong, wrong, clearly over the line, unacceptable."
The Republican congressman said the White House must refer the matter to the Office of Government Ethics for review. He said he and Democratic Oversight Leader Elijah Cummings are writing a letter to the office and he will also write to President Donald Trump about the matter.
"It needs to be dealt with," he told The Associated Press. "There's no ifs, ands or buts about it."
The Associated Press contributed to this report.