President Yoon Suk Yeol speaks during the sixth formal hearing of his impeachment trial at the Constitutional Court in Seoul, Feb. 6, in this photo provided by the court. Yonhap

Former Interior Minister Lee Sang-min denied Tuesday that he ordered cutting off power and water to major media outlets during the short-lived imposition of martial law or received such instructions from President Yoon Suk Yeol.

Lee made the remarks as a witness during the seventh formal hearing of Yoon's impeachment trial at the Constitutional Court, referring to allegations in the prosecution's indictment of Yoon that the president ordered him around midnight on Dec. 3 to cut off power and water to Hankyoreh, the Kyunghyang Shinmun, MBC and JTBC — left-leaning media outlets critical of Yoon — as well as opinion polling agency Flower Research.

"Such measures were completely excluded from the martial law (decree) so I don't think there was reason to give such instructions," Lee said.

"It was a known fact that the interior minister has no authority to command the police or the firefighting agency, and the president knew that better than anyone, so he would not have given me such form of instructions," he added.

Lee did acknowledge however that he saw a note on Yoon's desk headed with the word "National Fire Agency chief" and listing the names of the media outlets and the polling agency.

"I saw a few notes from afar inside the president's office and one of them mentioned the fire agency cutting off power and water," he said.

The minister also testified that he tried to stop Yoon from declaring martial law when he was called to the presidential office on the night of Dec. 3.

"After 11 Cabinet members had gathered, President Yoon reentered wearing a suit and we discouraged the president," he said. "President Yoon, however, said he is aware of its economic and diplomatic impact, and the political burden it would be, but that he had thought carefully and that a president's situation awareness and sense of crisis and responsibility were completely different from those of a Cabinet member."

Former Interior Minister Lee Sang-min, center, appears at the Constitutional Court in Seoul to attend the seventh hearing of President Yoon Suk Yeol's impeachment trial over his short-lived imposition of martial law in December, Feb. 11. Yonhap

Prior to Lee's testimony, Yoon asked the bench for a chance to speak.

He voiced his opposition to the Constitutional Court using as evidence the prosecution's reports on interrogations of key suspects in the martial law case, saying the testimonies are inconsistent because they were given to multiple investigation agencies.

Acting court President Moon Hyung-bae said he would raise the issue with the other justices.

The trial has entered its final stretch with only one more scheduled hearing on Thursday, though the court could still designate additional sessions.

Later Tuesday, National Security Adviser Shin Won-sik, who was also called as a witness, recalled that during a dinner with Yoon and others at a presidential safe house sometime between late March and early April, the president mentioned the need for an "exceptional measure."

"I understood it as the military needing to play a role in real politics," Shin said. "I didn't think as far as martial law, and expressed my opinion that it would not be appropriate in any event."

Shin, who was the defense minister at the time, also said he rejected the idea as "not very useful," based on his perceptions of history, the realities of the military and the public's political consciousness.

Baek Jong-wook, former third deputy director of the National Intelligence Service, and Kim Yong-bin, secretary-general of the National Election Commission, are scheduled to testify later in the day.

The two are expected to be questioned about Yoon's claims of election fraud, which he has said was one of the reasons for declaring martial law.

Yoon was impeached by the National Assembly in December on charges of inciting an insurrection through his short-lived imposition of martial law.

The Constitutional Court has been reviewing whether to uphold the impeachment and remove him from office or dismiss the impeachment and reinstate him.

Yoon is currently being held at a detention center ahead of a separate criminal trial on the insurrection charges.(Yonhap)