U.S. Republican vice presidential nominee Mike Pence called Russian President Vladimir Putin a "small and bullying leader" on Tuesday and condemned his actions in Syria, taking a harder line than Donald Trump at a contentious debate with Democratic rival Tim Kaine.

Pence's denunciation of Putin for his interference in the Syrian civil war and support for Syrian President Bashar Assad was a departure from the frequent praise of Putin by Trump, the Republican presidential nominee, who has called him a better leader than U.S. President Barack Obama and said he could work with him.

"The small and bullying leader of Russia is now dictating terms to the United States," Pence said. "The greatest nation on earth just withdraws from talks about a cease-fire, while Vladimir Putin puts a missile defense system in Syria."