Spicer said he believes Trump's daughter was "targeted" and that there are clear efforts to "undermine" her name due to Trump's policies.
"This is a direct attack on his policies and her name, so there's clearly an attempt for him to stand up for her because she's being maligned because they have a problem with his policies," Spicer said.
"Over the past year, and particularly in the last half of 2016, sales of the brand have steadily declined to the point where it didn’t make good business sense for us to continue with the line for now," Nordstrom said in a statement. "We've had a great relationship with the Ivanka Trump team. We’ve had open conversations with them over the past year to share what we've seen and Ivanka was personally informed of our decision in early January.”
From his personal twitter account, Trump today tweeted that Nordstrom treated his daughter "unfairly." Ivanka Trump said in an earlier statement that she was no longer going to be "involved with the management or operations of" her brand or the Trump Organization.
The tweet was then retweeted by the official POTUS account. Spicer did not directly respond to a question from reporters about the appropriateness of doing so.
A former White House ethics lawyer, Norm Eisen, who worked under Barack Obama, criticized the president today for his tweet about Nordstrom.
"He's using the power of the presidency to financially benefit one business and to harm another...to benefit his daughter," Eisen told ABC News. "He's sending a signal to the rest of the world, hey don't mess with me or my family. It's mafia-like."
Eisen suggested that Nordstrom should sue under unfair competition laws that prohibit the type of behavior displayed in Trump's tweet.
"I do believe Nordstrom has a colorful claim," he said. "This will be another place where the courts will remind him he's not above the law."
On Twitter, Eisen even offered to help Nordstrom should they decide to file suit. Eisen is an outspoken legal critic of the president and is already leading another lawsuit against him over the Emoluments Clause.
Nordstrom said last Thursday that it would no longer carry Ivanka Trump's clothing and accessories line.
"We've got thousands of brands –- more than 2,000 offered on the site alone," said a spokesperson for the Nordstrom, which has nearly 350 stores under various banners across North America. "Reviewing their merit and making edits is part of the regular rhythm of our business. Each year we cut about 10 percent and refresh our assortment with about the same amount. In this case, based on the brand’s performance we’ve decided not to buy it for this season."
"Neiman Marcus has a very small Ivanka Trump precious jewelry business which is comprised 100 percent of consigned merchandise (merchandise owned by the vendor). Based on productivity we continuously assess whether our brands are carried in stores, on our website, or both," a Neiman Marcus spokesperson said in a statement to ABC News.
“At TJX, we deliver great value on a rapidly changing selection of brand name and high quality apparel and home fashions. We aim to offer a merchandise mix that gives our customers a choice in what they may want to purchase. At this time, we continue to offer this line of merchandise. From time to time, we communicate with our stores about how to handle merchandise. The communication we sent instructed stores to mix this line of merchandise into our racks, not to remove it from the sales floor.” a TJX spokesperson said.
The Ivanka Trump brand said it continues to "expand" despite the action from the stores.
A spokesperson for the Ivanka Trump brand declined comment on the president's tweet in defense of his daughter's brand this morning.