GOP front-runner told CNN that "I think Islam hates us," adding, "We have to get to the bottom of it. There is an unbelievable hatred of us."
Asked whether he thought there was a "war between the West and Islam itself," Trump said, "It's radical, but it's very hard to define. It's very hard to separate. Because you don't know who's who."
Trump has already drawn intense criticisms, even from his own party, over anti-Muslim rants, calling on different occasions for a total ban on all Muslims from entering the United States.
The billionaire businessman said last November that "something nasty" is coming out of Islam.
The GOP front-runner has also refused to take back his unsubstantiated claim that he saw “thousands and thousands” of Muslims in the state of New Jersey cheering the collapse of the World Trade Center in New York on September 11, 2001.
Trump’s fiery comments have caused party rivals to step up attacks against him and some conservatives to label him a "fascist."
The White House hopeful also drew strong criticism for saying that he would require American Muslims to register in a database.
Over the past several months, the US tycoon has time and time again drawn fire for his tough speeches against migrants, Hispanics and other minority groups in America.
Less than a week until the Republican primary in Florida, a new Fox News poll finds Trump is trouncing rival Marco Rubio on his home turf there.
Meanwhile, reports say a group of US business moguls and politicians converged last weekend for a secretive meeting at a remote island to discuss ways to stop Trump.
Democratic presidential hopefuls Senator Bernie Sanders (L) and Hillary Clinton are seen on stage during a break in the broadcast of the Univision News and Washington Post Democratic Presidential Primary Debate at the Miami Dade College in Florida on March 9, 2016. (AFP)
US Democratic presidential hopefuls Hillary Clinton and Bernie Sanders have clashed on a number of issues during their latest debate in Miami, Florida.
The debate comes less than a week before the critical primary in Florida, which is home to a large Hispanic community.
Clinton and Sanders both courted the Latino vote, expressing support for comprehensive immigration reforms. But they blasted each other for anti-immigration positions over the past years; Press TV reported.
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