The relationship between President Donald Trump and Sen. Rand Paul (R-Ky.) continues to sour as the debate over the new Graham-Cassidy Healthcare bill continues to rage.

Paul has made it clear that he’s a definite “no” vote on the new Republican bill, saying that it’s not really a repeal, and is just another attempt at passing “Obamacare Lite,” and adding that it’s a like a “petty partisan bill that doesn’t fix the problem.”

On Wednesday, Trump fired a tweet across Paul’s bow, calling him a “negative force” when it comes to fixing healthcare.

“Rand Paul is a friend of mine but he is such a negative force when it comes to fixing healthcare. Graham-Cassidy Bill is GREAT! Ends Ocare!” tweeted Trump.

On Friday, Paul returned fire on the same platform, re-upping his stance that the Graham-Cassidy bill is Obamacare Lite, and adding that he won’t be “bribed or bullied” into supporting the bill.

“I won’t vote for Obamacare Lite that keeps 90% of the taxes & spending just so some people can claim credit for something that didn’t happen,” tweeted Paul. “Calling a bill that KEEPS most of the Obamacare “repeal” doesn’t make it true. That’s what the swamp does. I won’t be bribed or bullied.”

While Paul remains firm, some doubt his integrity in resisting this bill, as he had voted for the “skinny repeal,” which would have expanded medicare in his state of Kentucky.

Paul’s stance remains highly unpopular with many Republicans, however Paul seems to be planting his foot firmly. While Trump and Paul’s relationship has often been amiable, this wouldn’t be the first time Paul stood in the way of a Republican healthcare bill, and we could see the duo finally turn their backs on one another.