Donald Trump labels rival 'an idiot'

Trump also gave out US Senator Lindsey Graham's cellphone number during a campaign rally.

FILE: Donald Trump. Picture: AFP.

NEW YORK - Presidential hopeful Donald Trump persisted in his attacks on fellow Republicans on Tuesday, calling US Senator Lindsey Graham an "idiot" and giving out the South Carolina lawmaker's cellphone number during a campaign rally.

Trump, a real estate mogul and television personality, said in Graham's home state of South Carolina that he had heard the Republican senator call him a "jackass" in a recent interview.

Trump claimed Graham, who is also seeking the presidency in the November 2016 election, had called him several years ago looking for connections at Fox News and for campaign contributions.

"You know, I'm saying to myself, what is this guy, a beggar?" Trump said of Graham during the rally in Bluffton, South Carolina.

"He gave me his number, and I found the card. I wrote the number down. I don't know if it's the right number. Let's try it," Trump told the crowd before reading out a phone number with a Washington area code.

"He won't fix anything, but at least he'll talk to you," Trump said.

A phone call to the number by a Reuters reporter went to a voicemail message that said the number belonged to Graham.

Graham's presidential campaign confirmed the number was the senator's.

"Donald Trump continues to show hourly that he is ill-prepared to be commander in chief," Christian Ferry, Graham's campaign manager, said in a statement.

Trump has infuriated Republicans by criticising fellow members of the party and made many of them uncomfortable with harsh remarks about illegal immigration and other issues.

His latest dust-up involved criticising the war record of US Senator John McCain, an Arizona Republican who is close friends with Graham.

"I don't care if he drops out. Stay in the race, just stop being a jackass," Graham said of Trump on Tuesday in an interview with CBS News.

Ben Carson, another of the 16 Republicans seeking the presidency, said there was too much focus on Trump, The Washington Post said on Tuesday.

"For us to get caught up in a controversy of well, 'What did Donald Trump mean when he said that?' It just seems so petty to me," Carson said at an event in Virginia, the Post reported.