Republican Sen. Rand Paul spoke on Thursday as President Trump signed an executive order side-stepping rules put in place by the Affordable Care Act, and body language between the pair was all over the place.

In Trump's first year in office, the 45th president has had to meet with Paul on multiple occasions -- particularly in regard to the legislative branch's multiple attempts at passing a bill to repeal and replace Obamacare. In light of Capitol Hill's failure to make good on that Trump campaign promise, the commander in chief's signed order comes as a way to circumvent some Affordable Care Act rules -- and Sen. Paul said the action marks "the biggest free-market reform of health care in a generation."

Despite later giving Trump a thumbs up after he signed the order, Paul's reaction to Trump when the former billionaire businessman entered the room couldn't have been more different.

CSPAN's Jeremy Art shared the moment via Twitter:

Watch Rand Paul as President Trump enters the room. pic.twitter.com/yTzTc0Sy73 — Jeremy Art (@cspanJeremy) October 12, 2017

Paul and Trump have a contentious history dating back to when the two faced off on the Republican primary stage during the 2016 election. Trump and the senator, who was first elected in 2010, exchanged many a rhetorical blow during the campaign season -- with Trump calling Paul a "spoiled brat" and even questioning his presence on stage during one debate.

"Donald Trump is a delusional narcissist and an orange-faced windbag," the Kentucky senator once said during a 2016 Comedy Central appearance. "A speck of dirt is way more qualified to be president."

Click through to see images of Trump and Paul at the order signing:



8 PHOTOS Trump, Rand Paul exchange varied body language at order signing See Gallery Trump, Rand Paul exchange varied body language at order signing U.S. Senator Rand Paul (R-KY) gives President Donald Trump a thumbs up after Trump signed an Executive Order to make it easier for Americans to buy bare-bone health insurance plans and circumvent Obamacare rules at the White House in Washington, U.S., October 12, 2017. REUTERS/Kevin Lamarque U.S. Senator Rand Paul (R-KY) is given the pen after U.S. President Donald Trump signed an executive order to make it easier for Americans to buy bare-bones health insurance plans and circumvent Obamacare rules at the White House in Washington, U.S., October 12, 2017. REUTERS/Kevin Lamarque U.S. Senator Rand Paul (R-KY) listens as U.S. President Donald Trump speaks before signing an executive order making it easier for Americans to buy bare-bones health insurance plans and circumvent Obamacare rules at the White House in Washington, U.S., October 12, 2017. REUTERS/Kevin Lamarque Senator Rand Paul, a Republican from Kentucky, speaks before U.S. President Donald Trump, not pictured, signs an executive order on health care in the Roosevelt Room of the White House in Washington, D.C., U.S., on Thursday, Oct. 12, 2017. Trumpï¿½signed an executive order Thursday designed to expand health insurance options for some Americans, in a move that may also undermine coverage for those who remain in Obamacare. Photographer: T.J. Kirkpatrick/Bloomberg via Getty Images US President Donald Trump signs an executive order on health insurance on October 12, 2017, in the Roosevelt Room of the White House in Washington, DC. / AFP PHOTO / MANDEL NGAN (Photo credit should read MANDEL NGAN/AFP/Getty Images) U.S. Senator Rand Paul (R-KY) and U.S. President Donald Trump listen to remarks before signing an executive order making it easier for Americans to buy bare-bones health insurance plans and circumvent Obamacare rules at the White House in Washington, U.S., October 12, 2017. REUTERS/Kevin Lamarque Senator Rand Paul, a Republican from Kentucky, speaks before U.S. President Donald Trump, not pictured, signs an executive order on health care in the Roosevelt Room of the White House in Washington, D.C., U.S., on Thursday, Oct. 12, 2017. Trumpï¿½signed an executive order Thursday designed to expand health insurance options for some Americans, in a move that may also undermine coverage for those who remain in Obamacare. Photographer: T.J. Kirkpatrick/Bloomberg via Getty Images US President Donald Trump shows an executive order which he just signed on health insurance on October 12, 2017 in the Roosevelt Room of the White House in Washington, DC. / AFP PHOTO / Mandel NGAN (Photo credit should read MANDEL NGAN/AFP/Getty Images) Up Next See Gallery Discover More Like This HIDE CAPTION SHOW CAPTION of SEE ALL BACK TO SLIDE

Other social media users were quick to GIF-ify the moment:

The look on Rand Paul's face. Like he's sacrificing his firstborn son in exchange for #Healthcare#ExecutiveOrder. pic.twitter.com/4c5FB1x29A — Oliver Darko (@oliver_drk) October 12, 2017

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