Elon Musk publicly mused about creating a new political party this week, an idea that could escalate the billionaire's feud with his onetime ally President Trump.

Musk first floated the idea on Thursday. In between jabs at Mr. Trump, the billionaire posted a poll to X asking his 220 million followers if they think it's "time to create a new political party in America that actually represents the 80% in the middle."

A day later, Musk noted that 80% of respondents to the poll backed the idea.

"This is fate," he wrote Friday evening.

Musk then endorsed a fan's suggestion that he name it the "America Party." The name bears a resemblance to America PAC, the political action committee founded by Musk last year that was his main vehicle for spending $239 million to help elect Mr. Trump and other Republican candidates in 2024.

Starting a new political party is easier said than done. The Democratic and Republican parties, and some of the larger third parties, already have ballot access in virtually every state, so an upstart party that hopes to be competitive would need to navigate a web of state-by-state rules to get its candidates on the ballot.

And while Musk — the world's richest person — is legally allowed to pour unlimited money into his America PAC because it is organized as an independent super PAC, donations to formal political parties are capped at well under $1 million, per the Federal Election Commission's contribution limits for 2025-2026 federal elections.

It's not clear how serious Musk is about the idea of breaking with the Republican Party. Later Friday, the billionaire replied "Ok" to a person who argued "the best bang for your buck" is to get involved in GOP primaries. He also seemed to entertain a post that suggested reforming one of the main parties "from the inside out" instead of starting a third party, replying "Hmm."

Still, Musk's musings about starting a new political party could signal he plans to stay engaged in politics, and may try to challenge Mr. Trump's influence.

Musk said last month he planned on dialing back his political spending generally, saying at the time that he didn't "see a reason" to keep putting his money into politics, though he left open the possibility of getting involved again. His time leading the Trump administration's Department of Government Efficiency also came to an end last week, with Mr. Trump publicly expressing support.

But Musk began directly challenging Mr. Trump on Tuesday, calling the One Big Beautiful Bill Act — a sprawling domestic policy bill backed by Mr. Trump — a "disgusting abomination" and urging lawmakers to vote against it. The two men publicly sparred on Thursday, with Mr. Trump threatening to cut off subsidies to Musk's companies, while Musk claimed the president was ungrateful for the hundreds of millions he poured into helping the 2024 Trump campaign.

Musk entered the congressional fray at a delicate moment for the GOP. The party's domestic policy bill narrowly passed the House last month, but it still needs to go through the Senate, and if the upper chamber makes any changes, it will need to head back to the House again.

Musk offered a pointed suggestion Thursday afternoon to any congressional Republicans who may be unsure of whether to side with him or the president, writing on X: "Trump has 3.5 years left as President, but I will be around for 40+ years."