Walmart has apologized to Missouri Sen. Josh Hawley after a tweet from its official account said the Republican senator was a "sore loser" for planning to oppose the U.S. presidential election, HuffPost and other news sources reported Thursday.

After Hawley tweeted he planned to object to the Electoral College vote's certification for president-elect Joe Biden next week the Twitter account replied, "Go ahead. Get your two-hour debate. #soreloser."

Walmart blamed a staff member at its social media division for the now-deleted comment, saying the member had intended to publish the message from their personal verified account.

The hashtag #BoycottWalmart started to trend on the social media platform moments after it came out on the retailer's official Twitter account.

The 40-year-old legislator retaliated attacking Walmart's labor practices: "Thanks @Walmart for your insulting condescension...now that you have insulted 75 million Americans will you at least apologize for using slave labor?"

Walmart and other big U.S. retail companies like Amazon and Target pay above the government-required minimum wage.

Outgoing President Donald Trump and his allies have insisted since November that Biden's victory was the result of election fraud. Hawley's plan to oppose the Senate certification is the latest attempt from the Republican bloc to revoke the election.

Next week, the U.S. Senate and Congress will vote independently on whether to validate the Electoral College outcome which went 306-232 for Biden.

But Hawley's objection is expected to be dismissed since Democrats will hold the House and both chambers must accept a challenge.