The onetime newspaper editor said he felt he was "flying the flag" for Britain prepares to take the torch from King in January. And he knows Americans will be judging him, too.
"The whole of America will be waiting to see what I do with it. I don't want to let down Britain; I feel like I'm flying the flag a bit," said Morgan.
He'll get nowhere trying to be just like Larry King, so Morgan plans to do things differently. For one thing, he'll prepare for his interviews. And he said he won't be lobbing softballs at guests.
"I'm a different kind of interviewer," Morgan told the BBC. "I don't think anyone's ever accused me of being a softball interviewer."
Still, he's not looking for blood, he said.
"I'm not really after skewering people's flaws: I don't think that's what people want from a cable interview show at nine o'clock."
Americans probably "see me as they probably see Simon Cowell and Gordon Ramsay and the other British exports: as a tough-speaking, blunt Brit who has a bit of a sense of humor," Morgan said.