Republican vice presidential candidate Paul Ryan says that President Mitt Romney would be leading from behind and letting Congress fill in the details of his tax plan.

During a recent interview with the Christian Broadcast Network, Ryan refused to say which specific tax loopholes would have to be closed to pay for Romney's budget plan, which concentrates tax breaks on the wealthiest Americans.

"Is there a reason you guys aren’t naming specific tax loopholes?" CBN's David Brody asked Ryan.

"Yes, because we want to get it done," the Wisconsin Republican explained. "Look, I’ve been on the Ways and Means Committee for 12 years. I’m very familiar with how to make successful tax reforms take place."

He continued: "We want to say this is our vision, lower tax rates across the board for families and small businesses and work on the loopholes that are enjoyed by the higher income earners, take away their tax shelters so more of their income is subject to taxation. That lowers everybody’s tax rates."

"And we have to be able to work with Congress on those details, on how to fill it in and more to the point we don’t want to cut some backroom deal that they did with Obamacare where we hatched some plan behind the scenes and they spring it on the country. We want to do this in front, in the public, through congressional hearings with Congress so that we can get to the best conclusion with a public participation. That’s the process that works the best to ultimate success gets this done. That’s why we’re doing it this way."

Conservative Harvard economist Martin Feldstein determined that Romney would need to eliminate mortgage deductions and other loopholes for families making over $100,000 to make his tax plan work.

The Tax Policy Center, however, has concluded that it's is mathematically impossible to make the plan work without raising taxes on people making less than $200,000.

Watch this video from CBN's The Brody File, broadcast Sept. 17, 2012.