Sen. Elizabeth Warren attends a reception for the New England Patriots at the White House in April. Warren suggested last week that a bill granting Obama fast-track authority to complete a 12-country free trade bill could weaken U.S. financial regulations. (Jonathan Ernst/Reuters)

President Obama made his case for his free trade pact with Asia by directing some tough words at a traditional ally: Sen. Elizabeth Warren.

“She’s absolutely wrong,” Obama said of the Democratic senator from Massachusetts in an interview with Yahoo News that was posted Saturday.

Warren, who has strong support among liberal, pro-labor Democrats, suggested last week that a bill granting Obama fast-track negotiating authority to complete a 12-country free trade bill could weaken U.S. financial regulations that the president championed and helped put in place after the last deep recession.

She called the deal “an overlooked threat to the safety of our financial markets.”

Obama suggested that Warren’s critique was driven by politics and her desire to promote her populist brand.

“Think about the logic of that,” the president said of the senator’s criticism. “The notion that I had this massive fight with Wall Street to make sure that we don’t repeat what happened in 2007 and 2008. And then I sign a provision that would unravel it? I’d have to be pretty stupid. And it doesn’t make any sense.”

Obama has touted the 2010 financial reform bill as one of the major legislative achievements of his first term. He went on in the interview to dismiss Warren’s claims as “pure speculation.

“The truth of the matter is that Elizabeth is, you know, a politician like everybody else,” Obama told Yahoo. “And you know, she’s got a voice that she wants to get out there. And I understand that. And on most issues, she and I deeply agree. On this one, though, her arguments don’t stand the test of fact and scrutiny.”

The U.S. Senate will begin debate as soon as Monday on “fast track” legislation that will allow Obama to complete negotiations on the 12-country Trans-Pacific Partnership trade deal. Congress must then approve or reject the deal, but cannot modify it.

On Friday Obama defended the need for the deal in a speech at Nike headquarters in Oregon.

“We’re not going to be able to isolate ourselves from the world market; we’ve got to be in there and compete,” Obama said. “When the rules are fair, we win every time, which is why I’m such a strong supporter of world trade agreements. … It’s not a fair deal right now; I want to make it fair.”

He has also argued that if the United States doesn’t write the rules for the trade pact, China will fill the void.

Obama’s comments to Yahoo News weren’t the first time he has criticized Warren. Last month Obama said that Warren and other liberal critics were “wrong on” the trade deal.