Former Republican presidential nominee Mitt Romney stated that Republican presidential candidates Donald Trump, Texas Senator Ted Cruz, and Florida Senator Marco Rubio ought to release their taxes for “the last two years that have already been filed” and that there’s “good reason to believe that there’s a bombshell in Donald Trump’s taxes” on Wednesday’s “Your World with Neil Cavuto” on the Fox News Channel.

Romney began by saying that both Trump and Democratic candidate Senator Bernie Sanders (I-VT) were connecting with voters who were upset with the Washington, which hasn’t made progress.

He added, “I think there’s no question but that Donald Trump has the clearest path to become the Republican nominee. I think for the other people still in the race, their path is becoming a slimmer and slimmer opening, and they’re having a difficult time communicating to their supporters just how they could become the nominee. It’s not impossible. I think it’s very difficult for any one of the non-Donald Trump contenders to be able to be a real threat, unless perhaps the field narrows. The field narrowing would, I think, create an opening, but that doesn’t seem to be happening other than Jeb Bush, who I think really put country first by saying, look, I’m going to step aside, and let my supporters go to someone else who they feel is representative of the kind of views that the country needs.”

Romney then said, when asked about his lack of an endorsement for anyone so far, “Well, frankly, I’d like to see a number of things from the candidates, not just their positions on issues in some detail, and some candidates are more thorough in laying out what they’re going to do than others, but I’d also like to see their back taxes. I’d like to see where they filed their taxes in the last several years. I’m not talking about their taxes this year. I’m talking about the taxes that have already been filed with the IRS. And Donald Trump and Marco Rubio and Ted Cruz have [not] shown us their back taxes.”

Romney further stated that “the last two years that have already been filed” would “give us a real sense of whether these people are on the up and up, and whether they’ve been telling us things about themselves that are true or not.” He then said, “I think we have good reason to believe that there’s a bombshell in Donald Trump’s taxes.”

He explained, “I think there’s something there, either he’s not as anywhere near as wealthy as he says he is, or he hasn’t been paying the kind of taxes we would expect him to pay, or perhaps he hasn’t been giving money to the vets, or to the disabled, like he’s been telling us he’s been doing. And I think that’s — the reason that I think there’s a bombshell in there, is because every time he’s asked about his taxes, he dodges and delays and says, well, we’re working on it. Hey, we’re not talking about the taxes that are coming due this year. Of course they’re working on those. They won’t be ready for months. We’re talking about taxes already filed, back taxes. And my back taxes, when I ran in 2012, my back taxes, I put out in January of 2012. We’re now in late February and we still haven’t seen either Donald Trump’s, or Marco Rubio’s, or Ted Cruz’s taxes. And frankly the voters have a right to see those tax returns before they decide who our nominee ought to be.”

Romney said that the scrutiny over his taxes when he ran back in 2012 is “a good reason for getting these things out before the voters make their choices to who our nominee will be.” He continued, “I put my taxes out in January of 2012, and that gave people a chance to digest it, and decide whether I was going to be the nominee or not. And if in fact Donald Trump’s taxes, or Marco Rubio’s, or Ted Cruz’s, have some real problems in there, let’s get them out there and see them. But I think it’s pretty clear that, given Donald Trump’s dodging and weaving and delay, I think the last time he was asked about his taxes he said, well, it’s going to be a month. Look, people have a right to know if there’s a problem in those taxes before they decide.”

Romney further said of Trump “[T]he fact that he is so aggressive in avoiding any discussion of taxes — of his taxes, and is not willing to put them out so far, suggests that there’s something in there he doesn’t want us to see. By the way, any time you talk about money, Donald Trump likes to tell you how wealthy he is, how he’s worth billions of dollars. And the first time he was asked about his taxes on the ‘Today’ show, he said, you know, they’re beautiful, alright, they’re big and they’re beautiful. Well, great, let us see them. He likes to tell people how well he’s done. Why isn’t he willing to let us look at the tax returns? And that’s something — I mean, this was an issue in my campaign, that’s why I’m so sensitive to it. It’s an issue in my campaign. we’re going to select our nominee. We really ought to see, from all three of these fellows, what their taxes look like, to see if there’s an issue there. I think in Donald Trump’s case it’s likely to be a bombshell.”

Romney concluded, “You know, Donald Trump has said he’s the best in the country for the disabled veterans, and for the disabled generally. Well, if his taxes show that he hasn’t made any contributions to the disabled veterans, or to the disabled generally, that would be a big issue. So — and I’m not saying that’s the case. I have no evidence of that. But I’m just saying there are things that could be issues, and when people decide they don’t want to give you their taxes, it’s usually because there’s something they don’t want you to see.”

Follow Ian Hanchett on Twitter @IanHanchett