Nordstrom, the department store chain, said on Friday that it was dropping the Ivanka Trump line, a decision it said was based on sales performance. A campaign, using the hashtag #GrabYourWallet, which has encouraged shoppers to boycott products with ties to Mr. Trump, his family and his donors, called the Nordstrom announcement a victory.

It was not clear what prompted the president to criticize the company five days later. As Mr. Trump has noted several times, federal conflict-of-interest laws apply to other officials, but not to the president.

Nordstrom’s stock dropped briefly after the president’s Twitter post, then rose again.

Mr. Trump’s blast at the company came two days after his wife, Melania, filed a libel lawsuit describing her “multiyear term” as “one of the most photographed women in the world” — an apparent reference to her status as a candidate’s wife and now first lady — as a lucrative business opportunity.

DeVos brings along a sense of humor on her first day

A day after her narrow confirmation as education secretary, Betsy DeVos toured the department she now leads and delivered a speech to staff members and reporters.