(CNN) Commerce Secretary Wilbur Ross violated his ethics agreement and submitted a financial disclosure form that "was not accurate," according to the Office of Government Ethics.
Emory Rounds, the director of the Office of Government Ethics, wrote that Ross reported in his annual financial disclosure that he sold bank stock that other reports indicate he did not sell.
That meant "the filer was therefore not in compliance with his ethics agreement at the time of the report," Rounds wrote.
The watchdog group that drew attention to the report, Citizens for Responsibility and Ethics in Washington, said OGE declining to certify a report "does not normally happen."
"With OGE declining to certify, that's a pretty giant red flag," the group's spokesman, Jordan Libowitz, told CNN.
Richard Painter, a former ethics attorney for President George W. Bush, told CNN he has never seen a Cabinet member's financial disclosure form rejected in this way.
Instead, he said, agencies sometimes send a draft financial disclosure form to OGE for review. If issues arise, they are dealt with behind the scenes. Painter believes the fact that the Ross matter wasn't handled this way is a sign OGE is trying to send a strong message to Ross.
The document is a routine financial disclosure form posted online by OGE. The decision to decline it is dated February 15.
In a letter to the Commerce Department's in-house ethics official, Rounds wrote the 2018 financial disclosure report is "not accurate" and that Ross is "not in compliance with his ethics agreement at the time of the report." Rounds also wrote that it is his understanding that Ross's paperwork was being sent to the inspector general's office for review.
Ross said in a statement, "While I am disappointed that my report was not certified, I remain committed to complying with my ethics agreement and adhering to the guidance of Commerce ethics officials."
A December report from the Center for Public Integrity found Ross did not sell the holdings in BankUnited as required within 90 days after he was confirmed to lead the Commerce Department in February 2017.
Ross said he believed the stock had been sold but that there had been a miscommunication with his agent.
In his statement on Tuesday, Ross said the shares "were worth approximately $3,700, an amount that federal regulations deem de minimis and below the threshold of a possible conflict of interest."
"Therefore, even if a BankUnited matter had come before the Department while I owned the shares -- and I have not been made aware of any such matter -- I would not have been disqualified from working on it," he said.
When he learned of the issue in October, Ross said he ordered the shares to be sold.