However, Trump’s former United Nation’s ambassador has no immediate plans to endorse the former president, the source said, and will urge him to seek the support of Republicans and independent voters who have grown wary of him.

Haley’s announcement is expected to come hours after she lost almost every state on Super Tuesday, including California, a development first reported by the Wall Street Journal.

The former South Carolina governor was viewed as the last bulwark against the former president by anti-Trump Republicans, including veteran California GOP strategist Rob Stutzman.

The former advisor to former Gov. Arnold Schwarzenegger described himself as unsurprised but disappointed by Haley’s decision.

“Her candidacy was of great purpose. She’s now the leader of the faction of Republicans who do not want the Trump in the White House,” Stutzman said.

Trump initially faced a large field of candidates seeking to be an alternative to the former president, including Haley, Florida Gov. Ron DeSantis, former New Jersey Gov. Chris Christie and several others. Haley initially balked at forcefully confronting her former boss, but as the field winnowed, she grew more aggressive. And she frequently highlighted polling that showed she likely had a better chance against beating Democratic President Joe Biden in November than Trump did.

Haley’s positioning drew support from the suburban, college-educated and female voters who were once reliable GOP voters, and who cost the party support during Trump’s 2016 and 2020 elections, including in Orange County. She also won backing from traditional Republican donors and outside groups that buttressed her campaign, but they backed away after her string of losses, including in her home state of South Carolina.

Trump is on the verge of clinching the 1,215 delegates to win the Republican nomination later this month. However, Haley made history by being the first Republican woman to win primaries — in Washington, D.C., on Sunday, and in Vermont on Tuesday.