WATCH: White House press secretary mocks 'snorting' Trump for proposing pre-debate drug test

Donald Trump's call for Hillary Clinton to take a drug test before participating in this week's debate was met with brutal ridicule on Monday by White House Press Secretary Josh Earnest.

When asked to comment on Trump's proposal, Earnest sarcastically responded, "You’re telling me that the candidate who snorted his way through the first two debates is accusing the other candidate of taking drugs? That's a curious development in the campaign."

Earnest insisted that he wasn't actually trying to say that he believes Trump is on drugs and explained that he was only trying to have "a little bit of fun" with his comments.

Former Vermont Gov. Howard Dean originally said that Trump might be taking cocaine after he audibly sniffled throughout the first presidential debate. Dean later apologized, however, and said he didn't want to add more baseless speculation to this year's presidential campaign.

Check out the full video of Earnest below.