Republican 2016 U.S. presidential candidate businessman Donald Trump listens to a question at the first official Republican presidential candidates debate of the 2016 U.S. presidential campaign in Cleveland Thomson Reuters Republican presidential candidate Donald Trump said on Monday he supported the use of US ground troops to fight Islamic State militants in the Middle East.

Speaking on MSNBC's "Morning Joe" program, the billionaire businessman said it would take American soldiers to target the militant group, also known as ISIS or ISIL.

"They have great money because they have oil," Trump said. "Every place where they have oil I would knock the hell out of them.

"I would knock out the source of their wealth, the primary sources of their wealth, which is oil," he told MSNBC. "And in order to do that, you would have to put boots on the ground. I would knock the hell out of them, but I'd put a ring around it and I'd take the oil for our country."

In addition to cutting off ISIS' oil income, Trump said, the militants' money in the banking system would also have to be targeted, though he did not offer any details.

"You have to cut that off," he said.

Trump's comments follow last's week's first prime-time televised debate for Republican presidential candidates.

The real-estate mogul and television personality leads public-opinion polls, putting him at the top of the 17-person pack of Republicans heading into the 2016 election for the White House.

(Reporting by Susan Heavey; Editing by Bernadette Baum)