Republican presidential front-runner Donald TrumpDonald TrumpJeh Johnson is designated survivor for inauguration Fox News signs Nigel Farage, backer of Trump and Brexit Trump sworn in as 45th president MORE late Saturday blasted the announcement that former President Bill ClintonBill ClintonA path forward for Democrats in the Trump era Huckabee praises Clinton’s inauguration stop Clinton at inauguration: 'I will never stop believing in our country and its future' MORE will campaign for his wife, Hillary ClintonHillary Rodham ClintonHuckabee praises Clinton’s inauguration stop Sanders: This is a 'tough day for millions of Americans' Pelosi on Dems' approach to Trump: Look at Bush MORE.

The real estate mogul said the former president has a “penchant for sexism” in a tweet.

The Democratic front-runner said in an interview last week that Trump has “a penchant for sexism” after the billionaire said she “got schlonged” in losing to then-Sen. Barack Obama in 2008.

“It’s not the first time he’s demonstrated a penchant for sexism,” Hillary Clinton told The Des Moines Register. “Again, I’m not sure anybody’s surprised that he keeps pushing the envelope."

Trump later warned Clinton to "be careful as you play the war on women or women being degraded card."

Trump’s campaign also claimed that the Democratic front-runner bullied women to hide her husband’s “sexist secrets."

Trump later Saturday repeated his claim that Hillary Clinton does not have the stamina for the Oval Office, tweeting that he would “do far more for women than Hillary” and would “keep our country safe, something which she will not be able to do.”

“I’ve had so many women come up to me and say, ‘You’ve got to keep her out, she’s so terrible,’” Trump said early Sunday on Fox News.

This report was updated at 8:18 a.m.