President Donald Trump struck back at Utah Sen. Mitt Romney, a past Republican presidential nominee, Saturday, a day after Romney said he was “sickened” by the findings in the special counsel’s report on Russian interference in the 2016 presidential election.

Trump tweeted that if Romney spent as much time fighting Barack Obama, who Romney ran against in the 2012 presidential race, as he does fighting Trump, Romney could have “(maybe)” been president.

A video of news footage of Romney’s loss and Trump’s win accompanies the tweet.

After reading the report of special counsel Robert Mueller on Friday, Romney tweeted a statement, saying, “I am sickened at the extent and pervasiveness of dishonesty and misdirection by individuals in the highest office of the land, including the President.”

Romney said he was “appalled” that people working for the campaign welcomed help from Russia, that no one went to U.S. police about information obtained illegally by Russia and that the campaign chairman was working to promote Russian interests in Ukraine.

“Reading the report is a sobering revelation of how far we have strayed from the aspirations and principles of the founders,” Romney said.

Another past presidential hopeful said he, too, was sick.

But Mike Huckabee, former Arkansas governor who twice tried for the Republican presidential nomination, said it wasn’t Mueller’s report that made him ill. It was Romney.

Huckabee quote tweeted Romney’s statement about the report, saying he wasn’t as distressed by Romney’s treatment of Trump as he was that Romney could have been a Republican president.

“Know what makes me sick, Mitt?” Huckabee asked. “Not how disingenuous you were ... but makes me sick that you got GOP nomination and could have been @POTUS”.

Romney’s remarks were among the harshest denouncements of the president from a member of his own party. However, Romney wasn’t alone.

Republican John Kasich, a 2016 presidential candidate and former Ohio governor, called the report’s finding worse than any he’s seen in his career working in government.

“[Trump’s] behavior described in the #MuellerReport is more than disappointing. It’s unacceptable & not behavior we should expect from our president,” he said, later adding that, “America deserves better.”

This isn’t the first time in Romney and Trump’s contentious relationship that Trump has mocked Romney’s presidential loss.

In 2016, Trump tweeted that Romney had lost to a “failed president.”

More recently in January, after Romney wrote an op-ed criticizing Trump in The Washington Post, Trump responded on Twitter, wondering if Romney would be a “TEAM player” or follow in the shoes of former Arizona Sen. Jeff Flake, who took a stand against Trump before deciding against running for reelection in 2018.

“I won big, and [Romney] didn’t,” Trump said. “He should be happy for all Republicans. Be a TEAM player & WIN!”