Lawyers for former President Trump and his co-defendants said in a court filing on Monday it is "impossible" for them to secure a $464 million bond to appeal New York's fraud case against them.

Why it matters: If Trump and others can't secure the bond as required by New York law, they may be unable to appeal the damages and interest they were ordered to pay.

Catch up quick: Trump and his co-defendants were ordered to pay $464 million in damages and interest after being found liable for financial fraud. Trump is on the hook for $454 million of that amount.

• In New York, defendants in civil cases are required to post a bond worth at least 110% of the judgment amount in order delay paying the penalty as they appeal, so Trump's appeal bond total is $464 million.
• Trump's lawyers have asked an appeals court to delay the bond posting until his appeal of the case has run its court.

What's inside: In Monday's filing, Trump's lawyers said he has been unable to find a company willing to cover the $464 million bond.

• They said they've approached over two dozen companies through four separate brokers and have spent "countless hours negotiating" without securing an underwriter.
• "Defendants' ongoing diligent efforts have proven that a bond in the judgment's full amount is 'a practical impossibility,'" the lawyers wrote.

Flashback: Earlier this month, Trump posted a nearly $92 million bond to appeal the $83.3 million in damages a jury ordered him to pay to writer E. Jean Carroll for defamation by denying her sexual assault allegations.

• To do so, the bond was underwritten by insurance company Chubb, an international insurance provider based in Switzerland, but other terms of the bond, such as how much money or collateral Trump put down, were not disclosed.

The big picture: If he posts the bond in the New York civil fraud case, Trump could owe millions to a bonding company that posts the money on his behalf.

• Trump has until next week to post the bond and prevent New York Attorney General Letitia James from collecting the court-ordered damages while he appeals.

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Editor's note: This story has been updated with additional details.