"He denied that he had anything to do with the attack," CBS veteran correspondent Charlie Rose said, speaking earlier after interviewing Assad in Syria.
The full interview with the 47-year-old Syrian leader is scheduled to be shown tomorrow, the US network said in a statement.
During the interview, Assad "denied that he had anything to do" with the chemical weapons attack last month near Damascus that could prompt U.S. military action, but would not say whether he has access to the weapons of mass destruction, the "CBS This Morning" host said on "Face the Nation."
"He does accept some of the responsibility" for the attack that killed almost 1,500 Syrian civilians - including hundreds of children, Rose said.
"I asked that very question: 'Do you feel any remorse?' He said, 'Of course I do,' but it did not come in a way that was sort of deeply felt inside. It was much more of a calm recitation of anybody who's a leader of a country would feel terrible about what's happened to its citizens."
As the US Congress continues to debate whether to authorise President Barack Obama's request to carry out a limited military strike in Syria, the administration should provide what it says is mounting evidence that Assad - and not the rebels fighting to oust him - used chemical weapons, he reportedly told Rose.
More than once, Rose added, Assad brought up the US decision to go into Iraq on the grounds of what turned out to be false evidence of Weapons of Mass Destruction.
Though Assad told Rose he was not necessarily expecting the United States to intervene, he "suggested that there would be, among people that are aligned with him, some kind of retaliation if a strike was made."
But he "would not even talk about the nature of the response," Rose said. "He had a message to the American people that it had not been a good experience for them to get involved in the Middle East in wars and conflicts... that the results had not been good.
Syrian opposition and the West have accused President Assad's forces of using chemical weapons on August 21 in a Damascus suburb, a charge denied by the government.
The Obama administration has accused Assad's forces of killing 1,429 people in a poison-gas attack.
A week ago, Obama had announced his decision to go in for a limited military strike against the Assad regime to hold it accountable for the use of chemical weapons and sought Congressional authorisation for it.