People close to Jeb Bush are pushing back against rumors that the former Florida governor and Republican presidential candidate is preparing to endorse Libertarian presidential nominee Gary Johnson.

Bush, whose father and brother, Presidents George H.W. Bush and George W. Bush, have said they plan to sit out the 2016 presidential election, has made no effort to hide his disdain for GOP nominee Donald Trump.

Trump, who accepted his party's nomination in Cleveland on Thursday night, often targeted Bush with insults on the campaign trail and during debates, calling him "low energy" and driving him to an early exit from the primary campaign.

Responding to rumors on Twitter and in right-wing blogs, Bush campaign press secretary Kristy Campbell said speculation was "not accurate."

"I haven't decided how I'll vote in November – whether I'll support the Libertarian ticket or write in a candidate – but I do know there are a lot of things Republicans can do in the coming months to lay the groundwork for rebuilding our party and the foundation for a true conservative renewal in our country," Bush wrote in an op-ed in The Washington Post last week.

Johnson stoked the rumors in a CNN interview on Wednesday.

"I can't say that we haven't had conversations, but no push on the conversations," Johnson said, adding he did not initiate any negotiation between the two camps. "I want to protect the innocent here."

"You don't go from being Republican-elected, you don't go from being the Republican nominee to say, 'Hey, I'm supporting Gary Johnson,'" Johnson said. "You go to say, 'Hey, I'm going to look at his campaign.'"

Gary Johnson tells me he is "totally unaware" of the rumor that Jeb Bush is set to endorse him. — Olivia Nuzzi (@Olivianuzzi) July 22, 2016

A spokesman for Johnson's campaign did not return several requests for comment.

An endorsement from Bush would be a coup for Johnson, who has urged disappointed voters who resisted Trump and presumptive Democratic nominee Hillary Clinton to give him a fresh look.

As Trump prepared to formally accept the nomination in Cleveland on Thursday night, rumors swirled that some delegates were preparing to endorse Johnson, a last-ditch revolt that would strike at the heart of party unity efforts.

Several delegations whose votes for Sen. Ted Cruz of Texas were discounted in the Republican National Committee's formal tally Tuesday said they were upset their objections had been steamrolled.

Cruz's closest ally in Washington, D.C., Sen. Mike Lee, R-Utah, told Reason he hasn't ruled out voting for Johnson.