White House hopeful Sen. Bernie SandersBernard (Bernie) SandersOvernight Defense: Senate passes 0B defense bill | 3,000 US troops heading to Afghanistan | Two more Navy officials fired over ship collisions Senate passes 0B defense bill Dems fear lasting damage from Clinton-Sanders fight MORE (I-Vt.) called on Democratic presidential frontrunner Hillary ClintonHillary Diane Rodham ClintonBiden slams Trump over golf gif hitting Clinton Overnight Cybersecurity: Equifax hit by earlier hack | What to know about Kaspersky controversy | Officials review EU-US privacy pact Overnight Tech: Equifax hit by earlier undisclosed hack | Facebook takes heat over Russian ads | Alt-right Twitter rival may lose domain MORE to oppose the controversial free-trade agreement the Obama administration is negotiating with 11 Pacific nations.

Congress is currently considering legislation that would make it easier for the White House to complete its emerging deal, known as the Trans-Pacific Partnership (TPP).

“I would hope very much that Secretary Clinton will side with every union in this country, virtually every environmental group, many religious groups, and say that this TPP policy is a disaster, that it must be defeated, and that we need to regroup,” he said during an interview Sunday on CBS’s “Face the Nation.”

Sanders, who is running in the Democratic primary, has been a staunch opponent of legislation that would make it easier for the administration to complete the negotiations.

“I'm not saying trade is the only reason, but it is a significant reason why Americans are working longer hours for lower wages, and why we have seen our jobs go to China and other low wage countries,” he said.

The House dealt the White House a stinging blow on Friday, refusing to advance the legislation that would aide President Obama's negotiations.

Sanders voted against the Senate’s companion measure, which was approved in May.

He said Sunday that the House vote showed growing momentum against the TPP deal, which will be kept secret until it is completed.

“Don't you think it's a little bit silly for members of Congress to be voting yes on a bill that they haven't seen?” Sanders said. “That is one of many reasons to be voting against this piece of legislation.”

The Vermont senator wants Clinton to be more forceful in her stance on U.S. trade policy, which he believes benefits the wealthy at the expense of the middle class.

“Our trade policy has been for many years is to allow corporate America the shut down plants in this country, move abroad, hire people for pennies an hour, and then lead their products back into the United States,” Sanders said. “It is a failed trade policy, and I would hope that the Secretary joins Elizabeth Warren … and vast majority of Democrats in the Congress in saying, ‘No, we've got to defeat this piece of legislation.’”