Sen. Elizabeth Warren, D-Mass., one of the biggest critics of President Obama's proposed Trans-Pacific Partnership (TPP) trade deal, released a report Monday detailing "two decades of failed enforcement by the United States of labor and environmental standards" related to past trade agreements.

The White House is in the midst of unprecedented trade negotiations with 11 other nations, which President Obama says will enhance the economy at home and abroad by establishing new relationships with Pacific Rim countries.

But the text of the TPP deal is classified, and most congressional Democrats, along with labor unions, environmental groups and advocates of Internet freedom, oppose the deal on grounds that it would exacerbate income inequality, undermine key regulations and give corporations the power to sue governments in international courts over lost profits. Republican leaders in Congress, along with corporate lobbying groups like the U.S. Chamber of Congress, support the TPP.

Warren has been one of the most outspoken opponents, and as part of her strategy to fight the TPP, she released her 15-page report Monday, titled "Broken Promises," which explains why she believes the TPP is a mistake and accuses both GOP and Democratic administrations of failing to uphold provisions in previous trade agreements.

"Supporters of past trade agreements have said again and again that these deals would include strong protections for workers, but assurances without strong enforcement are just empty promises," Warren says in the report. "The facts show that, despite all the promises, these trade deals were just another tool to tilt the playing field in further of multinational corporations and against working families."

President Obama, on the other hand, has said the TPP will be "the most progressive trade bill in history," and will have "higher labor standards and higher environmental standards," along with "new tools to hold countries accountable."

In Vietnam, for example, the TPP would guarantee workers a minimum wage and the right to form unions for the first time ever. One-third of Nike's products are produced by workers in that country.

Warren, according to Obama, is simply "a politician like everybody else" and "absolutely wrong" on trade.

But Warren insists that similar statements have been made regarding other trade agreements, like the North Atlantic Free Trade Agreement.

"The history of these agreements betrays a harsh truth: that the actual enforcement of labor provisions of past U.S. [free-trade agreements] lags far behind the promises," says the report.

The United States currently has free trade agreements with 20 countries, but U.S. agencies or investigators have "identified significant problems with the use of child labor or other labor-related human rights abuses" in 11 of those countries, according to the report. Warren points out that Obama, like former presidents Bill Clinton and George W. Bush, has failed to effectively enforce promises to protect workers.

"We have two decades of experience with free trade agreements under both Democratic and Republican Presidents. Supporters of these agreements have always promised that they contain tough standards to protect workers," the report reads. "The rhetoric has not matched the reality."

The Senate is currently considering granting Obama "fast-track" authority on the legislation, which would bar Congress from amending any final trade agreement negotiated. Warren has introduced more than six amendments aimed at reining in the TPP, including one that would prevent fast-track powers from being used on trade deals which include language that would allow companies to sue governments over decisions that hurt their financial investments, according to Politico.