WASHINGTON — Sen. Elizabeth Warren said Congress should demand that President Obama release the draft text of a trade deal with Asian-Pacific nations before handing him fast-track authority to ease approval.

“We’re being asked to grease the skids for a deal that’s basically done but is being held in secret until after this vote,” the Massachusetts Democrat said in an interview Tuesday with Bloomberg Television.

Fast-track legislation under consideration in the Senate this week would allow approval of trade deals for the next six years without amendment or filibuster. That effectively lowers the threshold for Senate approval from 60 votes to a simple 51-vote majority.

Warren has become the Democratic Party’s most prominent critic of trade legislation, pitting her against Obama.

Warren declined to respond to criticism from the president, who’s called her “absolutely wrong” on trade.

“For me this is not personal,” she said. “This is basically what I’ve worked on all my life: what’s been happening to America’s middle class. This trade deal is part of it.”