Donald Trump referenced the size of his hands during heated discussion
Donald Trump was slammed by his peers last night, in the 11th Republican TV debate in the US election.
Four candidates seeking the parties presidential nomination faced off in an event organised by Fox news.
The frontrunner Donald Trump came under fire from Florida Senator Marco Rubio and Texas Senator Ted Cruz.
Mr Trump was repeatedly accused of being inconsistent on a number of issues including immigration and the war in Afghanistan.
He admitted he changed his stance on issues but said flexibility was a strength.
During last night's debate, Fox moderator Chris Wallace used graphics to illustrate the figures involved in Trump's planned savings proposals, and the candidate faced questions on those figures.
There were plenty of insults bandied about by the New York businessman, including "liar Ted" and "little Rubio".
At the start of the debate, in one of a number of strange moments, Mr Trump defended the size of his hands and then alluded to another part of his anatomy.
Mr Kasich said he was the "only grown up on the stage" and with the best prospect of beating Mrs Clinton.
News organisations on Youtube have compiled highlights videos - which include remarkable exchanges about candidates' body parts.
Meanwhile, former republican presidential candidate, Mitt Romney, has also weighed in on the Republican presidential race.
Mitt Romney described Trump as a 'misogynist', a phony and a conman, stating that he has neither the "temperament nor the judgement" to be President:
"Isn't he a huge business success? Doesn't he know what he is talking about - no, he isn't, and no he doesn't."
Trump responded: "Mitt is a failed candidate. He failed horribly. I backed him, you can see how loyal he is. He was begging for my endorsement.
"I could have said 'Mitt, drop to your knees' nand he would have dropped to his knees. He was begging."
However, Trump's rivals have all said they will back him if he is the Republican presidential nominee in November.
Florida Senator Marco Rubio, who launched some of the most scathing attacks on the billionaire businessman, said: "I'll support the Republican nominee," referencing the importance of keeping Democratic hopefuls Hillary Clinton and Bernie Sanders away from the White House.
Asked if he would do the same, Texas Senator Ted Cruz responded: "Yes, because I gave my word that I would," referring to a pledge candidates signed last year to back the eventual winner of the race.
Ohio Governor John Kasich was less certain, saying: "I kind of think before it's all said and done I'll be the nominee."
See the full debate from Fox News below: