Support for Republican presidential front-runner Donald Trump has dropped 12 percentage points in a week, according to a new Reuters/Ipsos rolling poll. It's the billionaire real estate mogul's largest decline since he began leading the GOP polls in July.

Trump garnered support from 31 percent of Republicans in Reuters' rolling poll, which was conducted over a period of five days and ended on Nov. 27. That's down from Trump's peak of 43 percent on Nov 22.

The drop can be partially attributed to comments Trump made about Muslims living in the U.S. following the terrorist attacks in Paris on Nov. 13, which killed 130 people and injured hundreds more. 

Trump told NBC News on Nov. 19 that he "would certainly" require all Muslims in the U.S. to be registered in a special database, and also increase surveillance.

Trump also falsely claimed he watched "thousands and thousands" of Arab Americans in New Jersey cheer while the World Trade Center fell, and he mocked a physically disabled reporter at a campaign rally on Tuesday, as HNGN previously reported.

Retired neurosurgeon Ben Carson also saw his numbers fall in the Reuters poll, receiving 15 percent support of Republicans.

Florida Sen. Marco Rubio and Texas Sen. Ted Cruz tied for third place with over 8 percent each, and Florida Gov. Jeb Bush came in with 7 percent.

Reuters surveyed 464 to 347 respondents between Nov. 22 and Nov. 27 and reported a credibility interval of 5.2 to 6.1 percentage points.