President Donald Trump's corporate endorsements make some companies "squirm a bit," The Washington Post reported.

The companies behind some of the president's favorite products, including Sharpies, Big Macs, and Diet Cokes – and White House fast-food faves like Burger King, McDonald's, Chick-fil-A and Wendy's – have mostly kept the brand-conscious president at arms length, the Post reported.

"It used to be that brands would love to get an endorsement from the president," Tim Calkins, who teaches marketing at Northwestern University's Kellogg School of Management, told the Post. "Now, if anything, I think these companies probably squirm a bit."

"It's unfortunate that that's what we've come to," CEO and chief brand strategist of Chicago-based No Limit Agency Nick Powills added about the non-response from companies that have been touted at the White House. "No matter what, you're at a celebration at the White House, and it should be something you [promote]. It's too bad that silence is the answer."

Consumer brands used to be eager to highlight their proximity to presidents, Nick Powills, CEO and chief brand strategist of Chicago-based No Limit Agency, told the Post, saying "It was almost like winning a Michelin star."

But companies have also taken stock of the dangers of associating with a president who is not shy about attacking business giants like Harley Davidson, Ford, General Motors, the NFL, and Amazon.

"The silence is deafening," Calkins told the Post. "Everybody is very nervous about how the administration might respond."

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