The hashtag #BoycottWalmart was among the top-trending topics in the United States on the social media site, racking up more than 50,000 tweets by mid-afternoon.

"Absolutely disgusting Walmart! No other president has ever been treated like this. I will not be shopping at Walmart. #BoycottWalmart," wrote Twitter user MarLee (@Mar_Lee_C).

"Wow! Walmart reveals it’s true colors and promotes POTUS45 impeachment with disgusting T-Shirt. #BoycottWalmart," tweeted Reeni Mederos (@ProphetReeni).

A spokesperson for Walmart told Reuters that the items were sold by "third-party sellers" on its open marketplace website and were not "offered directly by Walmart."

"We’re removing these types of items pending review of our marketplace policies," the spokesperson said.

A search of the Walmart website Tuesday showed no "Impeach 45" apparel available for sale online.

On June 27, Walmart announced that it was introducing a 3D virtual shopping tour on its website, as the retailer pours billions of dollars into beefing up its e-commerce business.

(Reporting By Amy Tennery; Editing by Susan Thomas)

By Amy Tennery