Donald Trump
Republican U.S. presidential candidate Donald Trump speaks during a Town Hall in Janesville, Wisconsin March 29, 2016. Reuters

Republican presidential frontrunner Donald Trump will no longer honour his pledge to support the GOP nominee no matter who earns it in July. Trump claimed that the Republican National Committee, the Republican party and the party establishment have treated him unfairly.

"I have been treated very unfairly," the bombastic billionaire real estate mogul told Anderson Cooper during a televised town hall event on CNN. According to The Associated Press, Trump also said he does not expect his chief rival, Texas Senator Ted Cruz, to support him if he wins the nomination. "I don't want him to do something that he's not comfortable with," he said.

In early September, Trump signed the non-binding loyalty pledge to the GOP promising to support the party's eventual nominee and to not run as a third-party candidate. "The best way for Republicans to win is if I win the nomination and go directly against whoever they happen to put up. And for that reason, I have signed the pledge," Trump said at the time. "So I will be totally pledging my allegiance to the Republican Party for the conservative principles for which it stands."

There were 17 Republican presidential candidates at the time Trump signed the pledge. The GOP field has narrowed down to three candidates: Trump, Cruz and Ohio Governor John Kasich. Trump has a significant lead over Cruz and Kasich with the number of delegates needed to reach the 1,237 mark for the nomination. The oft controversial frontrunner has 736 delegates, followed by Cruz's 463 and Kasich's 143.

Despite being poised to win the Republican nomination, Trump could face a bigger challenge in the general election. Polls from a number of news networks and polling organisations reveal Democrats Hillary Clinton and Bernie Sanders could readily beat Trump in November. Of the three remaining GOP candidates, Kasich appears to be the only one able to potentially beat Clinton or Sanders in a general election.