Sen. Claire McCaskill (D-Mo.) came away impressed by billionaire investor Warren Buffett after a lunch meeting Senate Democrats held with him Thursday.

During the meeting, Buffett, who is the second richest man in the world, recommended that wealthy Americans pay higher taxes.

The tip from the "Oracle of Omaha" came as Congress considers healthcare reform legislation and steep federal deficits.

McCaskill tweeted on Friday:

Meeting w/ Warren Buffet yesterdy was terrific.Funny,super smart, successful,optimistic,capitalist,grounded,humble,& a Democrat. Great combo

"He said rich people are not paying enough taxes," McCaskill said after the meeting Thursday. "It was interesting to see someone who is such an aggressive capitalist, who believes so much in our capitalist system, saying we’ve got the scales way too heavily toward people who are very, very wealthy."