BLOOMBERG EXCLUSIVE: Warren Buffett and Rep. Scott Rigell (R-VA) spoke with Bloomberg Television's Betty Liu in Omaha, NE during their first in-person meeting following Rigell's pledge to give 15% of his salary to help pay down the national debt.

Buffett said he would donate 15% of his income if 10% of Congress would, but that donations are ultimately insufficient and "what is effective is changing the law."

Buffett also blames Congress for Mitt Romney's 15% tax rate, saying "it's the wrong policy to have...he's not going to pay more than the law requires, and I don't fault him for that in the least."

Buffett on whether he would donate 15% of his income to the government:

"If you can get a significant percentage of Congress to do that, I would do it. If out of 435 in the House, the additional in the Senate, if 50 of them would do it, I would. 10% of Congress, sure."

Buffett on Mitt Romney's 15% tax rate:

"Exactly what I expected. He makes money the way I do. He makes money by moving around big bucks, not by straining his back and going to work, cleaning the toilets or whatever it may be. He makes it shoving around money. I make it shoving around money. If you look at the 400 highest incomes in the United States, the average is $220 million. Something like 90 of them are effectively unemployed. They have no earned income, and that number has gone up over the years. That will not solve the budget deficit, what I'm talking about. The truth is, I am paying a tax rate less than when I was making $15,000 a year."

Buffett on whether it's wrong of Romney to pay 15%:

"It is the wrong policy. Nothing wrong about him doing that. He will not pay more than the law requires. I do not fault him for that in the least, but i do fault the law that allows him and me, earning enormous sums to pay over all federal taxes at a rate that is about half what the average person in my office pays."

Buffett on the Republican presidential candidates and their tax plans:

"I think Republicans, like Democrats, have trouble breaking ranks, particularly when they're running for election. I do not know what they would do if they got in any way. There is history that shows campaign promises to not end up being law...somebody has to come forth. One way or another, we have to get this down to a place where the average deficit does not run 2% of GDP. That probably involves numbers around 19%, 20% on revenues. Almost everyone agrees on that, they just do not want to be the ones to step forward. I will cheer for the Republican or Independent or Democrat who comes up with a plan like that. You can argue about things around the edges, but then you have something that is workable. What we have now is not workable."

Buffett on whether Romney has better experience than Obama to run the country:

"If you look at the leaders of the past, Roosevelt, Lincoln, the great leaders -- they come from all different backgrounds. What is required is a real belief in what this country can do, and it can do it, and then the ability to garner support which will take support from both sides of the aisle. That will happen. I am optimistic about that happening, but I just hope it would happen quicker than it is happening."

Buffett on whether he sees any validity in Newt Gingrich's recent attacks on Romney:

"Romney did a lot of things in the private sector that are perfectly legitimate. I do not like buying businesses with lots of debt, but there is nothing immoral about it. In some businesses, they hired more people, in others they let people go... I see nothing specific about him. I think his tax rate is too low, but that is the fault of Congress, not his fault."

Buffett on supporting President Obama's millionaires tax:

My general theory is you should have a tax system where those making millions and millions of dollars, who are paying a much lower rate for one reason or another, get moved up to the rate that people think they are paying, in the mid 30's. There are about 80,000 taxpayers within that group paying that lower percentage of taxes. I would move those people up -- one of whom is me and another is Governor Romney. Move them up to the mid 30's where most of the people are.

Rigell on who he endorses:

"I have not...It is helpful to have more business people in Washington. My own preference is to have someone who has had business experience in the White House."

Buffett on Gingrich's recent surge:

"I think Romney hurt himself...losing ground in the past 10 days than Newt gaining. I have watched all the debates, self flagellation here. On both Monday and Thursday, Romney hurt himself. He did not have a good answer on taxes, but it will not be the determining factor on who will be president."

Buffett on whether he wishes that more Congressman would stand up to his challenge:

"Absolutely. Yes, but it's more than that. What I really admire about Scott, he is dedicated to getting a sensible relationship between revenue and expenses in this country. It is a tough issue to face. He and I in the first five minutes found we were within fractions of a point, virtually. We both feel we could tolerate a small gap between the two, but we know we need more revenues and we have to bring down expenses, and we know it has to be believable. And it has to be attacked right now."

Buffett on why it's so difficult to find common ground in Washington:

"Neither side wants to move first. The Democrats do not want to talk about talk about expenditures and the Republicans do not want to talk about revenues. They have their own constituencies, they do not want to break ranks with their own comrades. It is human dynamics, but it has to be done. Scott wants to do it, and he wants to do it now. I join him with that."

Buffett on whether he's trying to bring common ground to Washington with his challenge:

"That was more symbolic. We have a $1.20 trillion deficit. Contributions are not going to make a big difference. I think the American public wants to see a sign of any kind that the members of Congress take this as seriously as they should. It is it is symbolic and it says, we are going to get to work on this. It is not that contributions will amount to anything significant -- but it draws attention to it. The American people want to believe in Congress, but they do not believe in Congress. They see this important issue getting pushed off, each side blaming each other. I do not want to look back at all, I just want to look forward."

Rigell on whether he's disappointed that more members of Congress haven't stepped up to Buffett's challenge:

"We are headed in the right direction, certainly in the Republican conference, and I hope across both sides of the aisle in recognizing that leaders must step up and we must lead by example."

Buffett on expanding his challenge to Wall Street and corporate America:

"I would rather just have a policy change. If I have $1.20 trillion to work on -- it would be nice to do it that way, but how many would do it? The press would focus on who did not do it. I do not see that as a way to get to where we need to be. You would see far more that would not do it than would unfortunately...it is more about getting organized. We need to change the law."

Rigell on whether he would agree to tax the wealthy more in order to generate more needed revenue for the government:

"If there were a comprehensive effort that included expenses going down, reduced to the 19%, 20% for me, I think we would have to look at that."