A group of independent auditors is demanding an additional $12.5 million to conduct an audit of Donald Trump’s presidential campaign, a move that could further inflame the feud between the former President and the GOP establishment.

In a letter released Wednesday, the Citizens for Responsibility and Ethics in Washington, DC, accused the Trump campaign of “an unprofessional, unethical and illegal campaign that has been characterized by a pattern of fraud, waste and abuse.”

“It is time for the American people to have their say on how their money is being spent,” Credo Executive Director Matthew Miller said in a statement.

“If the Trump Campaign is able to hide its criminal activity, and if the Trump Administration is unable to protect the Trump family’s assets, the American public will be left to the whims of an inexperienced campaign manager who has no integrity.”

Credo is a watchdog group of more than 100,000 individuals who work to hold members of the executive branch accountable.

The group is led by Miller, who has long fought to get Trump to release his tax returns, despite President Trump’s repeated insistence that he will not.

The letter was also signed by Republican House Speaker Paul Ryan and Senate Majority Leader Mitch McConnell.

“This is a very important issue and we need to be able to have a meaningful and transparent process to answer these questions,” Miller said.

“It is clear from these documents that the Trump Organization has been a clear fraud for many years and now we are seeing an opportunity to hold the Trump organization accountable for their actions.”

Miller told CNN on Wednesday that he expects the Trump team to provide the $12-million request in a short time.

“I think that’s going to happen pretty quickly,” he said.

Miller said the group’s request is unrelated to a report released last month by the Congressional Budget Office that found that Trump’s campaign would lose $17 million if it did not provide a list of foreign donors, including $5.7 million from foreign governments.

The report was published after the FEC rejected a request from the campaign to disclose the list.

Miller also said the auditors have not identified the money that was used to pay for travel for Trump’s family members, and the campaign’s refusal to release the list has led the group to believe that the campaign did not comply with federal laws and the law regarding foreign bribery.

Miller has long criticized the Republican Party for not holding candidates accountable for illegal campaign spending, which includes spending by foreign nationals on behalf of a candidate’s campaign.

In 2016, Miller wrote a letter to the party’s National Committeewoman that accused party leaders of engaging in “a pattern of illegal, immoral and unethical conduct.”

He said the party should be ashamed of its behavior.