Trump Jr admitted his Mitt Romney attack was 'not some thought-out strategy': report
Donald Trump Jr. appears on Fox News (screen grab)

Donald Trump, Jr. does not apparently think through all of his utterances on Twitter.

The first-son of Twitter's most infamous former user lashed out at Sen. Mitt Romney (R-UT) for concluding Donald Trump incited the January 6th insurrection at the U.S. Capitol during his father's second impeachment trial.

"Mitt Romney is forever bitter that he will never be POTUS. He was too weak to beat the Democrats then so he's joining them now. He's now officially a member of the resistance & should be expelled from the @GOP," he wrote, tagging the Republican National Committee account.

According to Wall Street Journal reporter Michael Bender's new book Frankly We Did Win This Election, Republican National Committee Chair Ronna Romney McDaniel was soon on the phone discussing her uncle.

"You know I can't just kick him out of the party, right?" McDaniel reportedly said, according to an account of the book by Business Insider's Grace Panetta.

"I'm just f*cking with him," Trump, Jr. reportedly replied. "This is not some thought-out strategy coordinated with the Republican caucus."

This wasn't the only time Trump, Jr. has complained about Romney on social media.

And Trump, Jr. has shared thoughts about the Utah Senator on Instagram.

Although Trump, Jr. once liked Mitt Romney and his wife Ann.