Malaysian Anti-Corruption Commission (MACC) chief Abu Kassim Mohamed will instruct for a police report to be filed against articles in the media citing information obtained from its personnel.
"Let me be very clear: if this is true, it will not be tolerated and action will be taken.
"No statement by any individual should be presented by the media as the official position of MACC on these cases (related to Prime Minister Najib Abdul Razak) unless it has been released by MACC's official strategic communications division upon my approval," he said.
He also said MACC officers must uphold the highest ethical standards and would be held to account for the oaths of office that they have sworn.
Abu Kassim reiterated that MACC is not disputing nor challenging the attorney-general’s decision to clear the prime minister.
"As stated yesterday, our referral to MACC's operations review panel is a standard operating procedure as part of the process of closing any case.
"For the sake of clarity, the attorney-general's powers over all criminal proceedings are conferred on him by Article 145(3) of the federal constitution.
"These powers are absolute and cannot be challenged by any authority," he said.
On Tuesday, attorney-general Mohamed Apandi Ali cleared Najib over the cases involving the RM2.6 billion and SRC International's RM42 million.
The following day, MACC special operations division director Bahri Mohd Zin told the Star that the commission would most likely appeal the decision.
He also described the cases as being "straightforward".
His remarks were seen as contradicting Apandi's statement that MACC admitted to having found no evidence of corrupt practices.
MACC came under the spotlight after the Wall Street Journal and whistleblower website Sarawak Report exposed the transactions into the prime minister’s private bank accounts based on leaked documents last July.
Drama then engulfed the commission as the police cast a dragnet for those who leaked the documents, while MACC held special prayers to seek divine guidance and protection.
Yesterday, Malaysiakini quoted sources familiar with the investigations as claiming that MACC recommended three charges against the prime minister under Section 403 of the Penal Code.
Today, Reuters reported that a source claimed the AG had ignored MACC's advice to initiate legal action.
Najib has repeatedly denied having committed any wrongdoing or abusing public funds, attributing such allegations to those plotting to topple him.