Trump says he'll 'fight' GOP Freedom Caucus members in 2018 if they don't 'get on the team'

President Donald Trump issued a threat to members of the House Freedom Caucus on Thursday in which he warned them of possible primary challenges if they don't line up to back his agenda.

"The Freedom Caucus will hurt the entire Republican agenda if they don't get on the team, and fast," the president tweeted. "We must fight them, and Dems, in 2018!"

Trump has previously criticized the Freedom Caucus for nuking House Speaker Paul Ryan's proposed health care plan, which died without receiving a vote last Friday. This marks the first time, however, that the president has suggested that he will back primary challenges against him if they keep bucking his agenda.

When asked by CNN reporter Jeremy Diamond whether Trump would really try to primary the Freedom Caucus in 2018, White House spokeswoman Sarah Huckabee Sanders said that "the president's tweet speaks for itself."