WASHINGTON (AP) — Two of the Democratic Party’s most vocal opponents of strengthening President Barack Obama’s hand in trade deals are taking issue with his recent criticism and are calling on him to make public the draft text of a still incomplete deal with 11 other Pacific rim nations.

Sens. Elizabeth Warren of Massachusetts and Sherrod Brown of Ohio sent Obama a letter Saturday disputing his characterization of their position as “dishonest.” They said that while members of Congress can read the draft text of the Trans-Pacific Partnership agreement, they are legally prevented from discussing it openly and the public is barred from examining it.

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The letter escalates what has been an increasingly personal confrontation between Obama and his critics, most of them liberal Democrats and the heads of organized labor who have traditionally stood behind the president’s economic policies.

Obama has been stepping up his trade policy push, eager to make liberalized commerce in the Asia Pacific region and in Europe signature achievements of his last two years in office.

Obama is first seeking so-called fast-track authority to give him more freedom to complete the trade deals. The Trans-Pacific Partnership would be the biggest trade deal for the U.S. and includes countries such as Japan, Chile and Vietnam. Under fast-track authority Congress would set the parameters for a deal, but it could only approve or reject a final agreement, not amend it.

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The issue, which has broad Republican and corporate support, has deeply divided Democrats, many of whom say it will cost American jobs and lower environmental standards.

Warren, from liberal Massachusetts, and Brown, from union heavy Ohio, have been among the sharpest critics, arguing that the Trans-Pacific deal is secret and would benefit businesses over workers.

Without singling them out by name, Obama lashed out at them over the last few days, calling their arguments dishonest.

“Every single one of the critics who I hear saying this is a secret deal, or send out emails to their fundraising base that they’re working to prevent this secret deal, could walk over today and read the text of the agreement,” Obama said Friday

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