The United States will boost its network of trade advisers to give a stronger voice to public health, development and consumer safety experts, Trade Representative Michael Froman said on Tuesday.

In a speech aimed at combating domestic opposition to free trade deals, Froman said increasing exports created more and better-paying jobs and urged Americans to get behind the Trans-Pacific Partnership, or TPP.

The TPP, currently being negotiated among 12 Pacific Rim countries, is under fire from interest groups ranging from unions and environmental lobbyists, who fear an erosion of U.S. standards, to conservative Republicans wanting a bigger role for Congress in deciding trade priorities.

"Skeptics need to assess what a world without TPP would mean," Froman said in a speech at the left-leaning Center for American Progress think tank.

"The world without TPP is a world with lower labor standards, weaker environmental protections and fewer opportunities for job growth."

Froman said a new public interest panel would be added to a network of trade advisory committees that already includes groups representing issues like labor, the environment, and industry sectors.

All advisory committee members have access to the text of U.S. negotiating proposals.

Lobby groups said the balance of the advisory committee was still skewed toward commercial interests and the change would not help educate the public due to confidentiality constraints for those sitting on the committees.

"The public has zero access to negotiating texts - even though corporations and the countries with whom the U.S. is negotiating do - and is therefore handcuffed in making meaningful suggestions," said Robert Weissman, president of Public Citizen, which is part of a campaign against the TPP.

Froman also urged Congress to move forward with giving the White House power to fast-track trade negotiations.

Several senior Democrats have balked at a bill currently before Congress that would allow the Obama administration to submit free trade agreements to lawmakers for an up-and-down vote, without amendments. Some Democrats are working on an alternative version with stronger provisions against currency manipulation and more worker safeguards.

"We are eager for Congress to step forward and update its role in trade negotiations, to make clear which members or committees should be involved, how those consultations should be conducted and what rules of transparency should apply," Froman said.