Warren Buffett has issued a challenge to Republican lawmakers opposed to raising taxes to help pay down the nation's debt: He'll match dollar for dollar any of their voluntary debt-reduction contributions to the IRS, the multibillionaire tells Time magazine.

The Oracle of Omaha said he would be even more generous with Senate Minority Leader Mitch McConnell, saying he'd triple anything the Kentucky Republican ponied up.

"It restores my faith in human nature to think that there are people who have been around Washington all this time and are not yet so cynical as to think that [the deficit] can't be solved by voluntary contributions," Buffett told Time with, the magazine adds, "a chuckle."

Recall that in August, Buffett drew attention (and fire) for a New York Times op-ed in which he wrote, among other things, that he paid a lower tax rate than his secretary.

"My friends and I have been coddled long enough by a billionaire-friendly Congress," he wrote. "It's time for our government to get serious about shared sacrifice."

McConnell, whose net worth has been estimated at $10 million, later tweaked Buffett, telling him to "send in a check" if he was feeling "guilty" about paying too little in taxes.

Following up with a piece of legislative mocking, Sen. John Thune, a South Dakota Republican, introduced his version of the "Buffett Rule Act," designed to let all Americans filing tax returns donate "no less than $1" into a debt-reduction fund. (The Senate killed it in December, and a House version died in committee.)

Responding to Buffett's latest comments, McConnell's office released this statement today:

"Sen. McConnell says that Washington should be smaller, rather than taxes getting bigger," McConnell spokesman Don Stewart said. "And since some, like President Obama and Mr. Buffett want to pay higher taxes, Congress made it possible for them to call their own bluff and send in a check. So I look forward to Mr. Buffett matching a healthy batch of checks from those who actually want to pay higher taxes, including congressional Democrats, the president and the DNC."

Who were the 50 richest members of Congress in 2011?