Republican front-runner Donald Trump on Thursday bowed to pressure from the party establishment and signed a pledge not to run as an independent candidate in the November 2016 presidential election, despite earlier refusals to rule out a third-party bid.
"I see no circumstances under which I would tear up that pledge," the real estate magnate told reporters at Trump Tower in Manhattan.
His signature is seen as a victory for the Republican establishment because an independent Trump candidacy in the November 2016 election would splinter support for the party.
Trump had previously refused to rule out a third-party bid. The billionaire, who leads opinion polls, has upset mainstream Republicans with his brash style and unusually personal attacks on rival candidates. An independent Trump candidacy could split support for the Republican Party and give the Democrats a boost.
One of Trump's key rivals, Jeb Bush, the former Florida governor, told ABC's "Good Morning America" television program that he would back Trump if the businessman-turned-politician won the party's nomination and Hillary Clinton is the Democratic nominee.
Trump, on the same program, also said he would back Bush over Clinton.
Reuters/Ipsos polling shows Trump with support among nearly 31 percent of self-identified Republicans as of Sept. 1, with Bush garnering support among nearly 12 percent, behind former neurosurgeon Ben Carson.
The RNC has asked its pool of 17 candidates to sign a loyalty pledge to ensure future party unity.
Republican presidential candidate Chris Christie, the New Jersey governor, urged Trump to cut the "pre-Labor Day Weekend drama" surrounding the pledge.
"Every candidate has to make the decision about do you really want the nomination of our party or do you want to have it both ways," he told Fox News Channel’s "America’s Newsroom" TV show. "This is just a little too much drama. Enough," he said.