NBC’s Savannah Guthrie asked Clinton in an interview taped Thursday and aired Friday whether he feels Romney’s overseas investments are a “legitimate line of attack” and “relevant to his fitness to be president.”

“Oh, yes I do. I think, for one thing, it’s just as relevant as the going over my record as governor got when I ran for president,” Clinton said in the interview on the “Today” show. “I’d been governor for a dozen years. And because he’s put it at the forefront. He’s said basically, ‘I’d be a better president because I know how to create jobs because that’s what I did.’ And he’s going to take credit for running a successful Olympics, for example. So then all your work life before you run for president is relevant, and I think that will be relevant.”

But he added that Romney’s decision not to release his tax returns, unlike other former candidates, “perplexed” him. “That struck me as a little odd,” Clinton said.