Former U.S. president Donald Trump is in panic mode as the deadline approaches to secure a half-billion dollar bond  to appeal his civil fraud case in New York, according to multiple sources familiar with his thinking.

Trump’s lawyers acknowledged Monday that he was struggling to find an insurance company willing to underwrite his US$454 million bond. Privately, Trump had been counting on Chubb, which underwrote his US$91.6 million bond to cover the E. Jean Carroll

 judgment, to come through, but the insurance giant informed his attorneys in the last several days that that option was off the table.

Trump’s team has sought out wealthy supporters and weighed what assets could be sold – and fast. The presumptive GOP presidential nominee himself has become increasingly concerned about the optics the March 25 deadline could present – especially the prospect that someone whose identity has long been tied to his wealth would confront financial crisis.

Trump has continued to privately lash out at the New York Attorney General Letitia James  and Judge Arthur Engoron  over the matter, these sources told CNN. (James provided a 30-day grace period after Engoron ruled.)

Shortly before 6:30 a.m. Tuesday, Trump took those grievances public, posting on his social media platform eight times within two hours about the deadline, arguing that he shouldn’t have to put up the money and worrying that he “would be forced to mortgage or sell Great Assets, perhaps at Fire Sale prices, and if and when I win the Appeal, they would be gone.”

“Does that make sense? WITCH HUNT. ELECTION INTERFERENCE!” the former president wrote.

“These baseless innuendos are pure bullsh*t,” Trump campaign spokesman Steven Cheung said in a statement Tuesday. “President Trump has filed a motion to stay the unjust, unconstitutional, un-American judgment from New York Judge Arthur Engoron in a political Witch Hunt brought by a corrupt Attorney General. A bond of this size would be an abuse of the law, contradict bedrock principals of our Republic, and fundamentally undermine the rule of law in New York.”

As Trump and his legal team wait to see whether an appeals court will pause the judgment as he appeals it, or allow him to pay a smaller bond of US$100 million, he has privately expressed opposition to any path concerning filing for bankruptcy, and it remains the least likely for now, one person familiar with the talks told CNN.

But his lawyers told the New York appeals court on Monday that he has approached 30 underwriters to back the bond, and the former president himself said on Truth Social he thought it was “practically impossible” for him to post the amount. Potential underwriters are seeking cash to back the bond, not properties, according to Trump’s lawyers.

The bond stems from Engorons ruling last month, which ordered Trump to pay US$355 million in disgorgement, or “ill-gotten gains,” in the case brought by James. The judge wrote in his opinion that Trump and his co-defendants -- including his adult sons -- were liable for fraud, conspiracy and issuing false financial statements and false business records, finding that the defendants fraudulently inflated the value of Trump’s assets to obtain more favorable loan and insurance rates. The amount Trump owed surpassed US$450 million with interest included.

In order to stop the state from enforcing the judgment, Trump has to post a bond to be held in an account pending the appellate process, which could take years to litigate.

Although Trump did post a US$91.6 million bond earlier this month as part of his appeal in the Carroll defamation case, Gary Giulietti – an insurance broker who testified for Trump during the civil fraud trial – said some of the biggest underwriters have internal policies that limit them from securing a bond in excess of US$100 million.