Washington (CNN) President Barack Obama is locking horns with one of his most prominent progressive critics on trade policy, calling out Massachusetts Sen. Elizabeth Warren as "wrong" in her opposition to a proposed trade deal with Asia.

"I love Elizabeth. We're allies on a whole host of issues. But she's wrong on this," Obama says in an interview with MSNBC's Chris Matthews at the Fairfax Chamber of Commerce, scheduled to air Tuesday night.

"I would not be doing this trade deal if I did not think it was good for the middle class. And when you hear folks make a lot of suggestions about how bad this trade deal is, when you dig into the facts they are wrong," Obama said.

It's the latest salvo in the continuing confrontation between the President and his party's left flank, which remains staunchly opposed to legislation that would give Obama the authority to fast-track trade deals -- like the pending Trans-Pacific Partnership -- through Congress with minimal interference from lawmakers.

Unions, which make up the core of the progressive movement, have expressed concerns that a new trade deal could deplete jobs in the U.S.

While leaders in Congress reached a tentative deal on the measure last week, that hasn't stopped congressional Democrats from voicing their skepticism.

Warren joined a handful of other Democratic lawmakers and union and environmental activists last week in a rally outside the Capitol against the fast-track legislation, and has said the agreement is "going to help the rich get richer and leave everyone else behind."

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Democratic Rep. Sandy Levin of Michigan said in a statement last week that the "negotiating objectives [in the deal] are obsolete or woefully inadequate."

"We can't expect to get the best deal if we are not asking for the right things," he said.

Obama is expected to focus on his message of competition and having learned lessons from the past in the interview with Matthews. Obama's been defending his administration's approach since last week.

"The politics around trade has always been tough, particularly in the Democratic Party," he conceded at a press conference on Friday, "because people have memories of outsourcing and job loss."

Obama says his administration insists the final TPP agreement will be fair to American workers and help promote American products abroad.

With Japanese Prime Minister Shinzo Abe coming to Washington next week, the Obama administration is under pressure to pave the way for a TPP deal.

"It would be good if I could reach an agreement during my meeting with the president, but when you climb a mountain, the last step is always the hardest," Abe told The Wall Street Journal on Monday. "Ultimately, what needs to happen is for both countries to make a political decision" to address these sensitive areas."

Abe said the gaps between the U.S. and Japan are narrowing, but more work needs to be done.

If the fast track authority bill passes, that could go a long way towards assuring the U.S.'s international partners that any deal reached by diplomats at the negotiating table can be implemented without interference from Congress.

In his press conference on Friday, Obama used Japan as an example for why a trade deal with Asia is necessary to ensure American products can compete in the world's markets.

"Now, the last time I checked, if you drive around Washington, there are a whole bunch of Japanese cars," Obama said. "You go to Tokyo and count how many Chryslers and GM and Ford cars there are."

"So the current situation is not working for us," he added. "And I don't know why it is that folks would be opposed to us opening up the Japanese market more for U.S. autos, or U.S. beef. It doesn't make any sense."

The issue of trade has become a point of contention on the 2016 campaign trail, where some potential Democratic contenders are using the issue to draw a sharper distinction between themselves and front-runner Hillary Clinton.

"Bad trade deals have sent American jobs and American profits abroad," former Maryland Gov. Martin O'Malley said at a speech on Thursday. "We must stop entering into bad trade deals-bad trade deals like the Trans-Pacific Partnership-that hurt middle-class wages and ship middle-class jobs overseas. And we certainly shouldn't be fast-tracking failed deals."

Sen. Bernie Sanders, D-Vermont, another opponent of the proposed trade deal with Asia who is considering a run for the presidency, called on Clinton to take a stronger stance against TPP.

"My strong hope is that Secretary Clinton and all candidates, Republicans and Democrats, will make it clear that the Trans-Pacific Partnership should be rejected and that we must develop trade policies that benefit working families, not just Wall Street and multi-national corporations," he said in a statement.