President Obama on Tuesday began trying to sell Congress on the recently signed Trans-Pacific Partnership, but a top Republican senator immediately said the deal falls “woefully short” of success.

"The United States should not settle for a mediocre deal that fails toset high-standard trade rules in the Asia-Pacific region for years to come,” said Orrin Hatch, chairman of the Senate Finance Committee. “A poor deal risks losing a historic opportunity to break down trade barriers for American-made products.”

Negotiators from the United States, Japan and 10 other countries agreed on the complex trade deal Monday, after more than five years.

On Tuesday, Obama met with business and agricultural leaders at the Department of Agriculture. The site of the meeting reflects the urgency that farm groups have attached to the deal to remove tariffs and other trade barriers and increase exports ranging from meat and poultry to grains and cotton.

Obama emphasized that the deal, estimated to impact roughly 40 percent of the global economy, would eliminate or reduce more than 18,000 tariffs that participating countries impose on U.S. exports.

The reduction of those tariffs will lower the price that international consumers pay for U.S. goods. For example, Obama said Japan currently puts a 38 percent tax on American beef and Malaysia currently puts a 30 percent tax on American auto parts.

"If the tariffs are down, if the taxes are down on goods made in America, that means U.S. companies are investing here and are able to sell over there without a disadvantage. That's what American leadership looks like in the 21st century," Obama told reporters at the end of the closed-door meeting.

Leaders of trade groups representing the film, travel and technology industries were among those who attended the meeting with Obama and Agriculture Secretary Tom Vilsack. One of the administration's selling points is that it will put pressure on China to match various safeguards and openness to competition that's written into the agreement.

It will be weeks before the full scope of the agreement announced Monday is known, but several labor groups are worried that it will result in American jobs sent to countries with lower wages and less stringent labor and environmental standards.

Earlier this year, Hatch championed Trade Promotion Authority, a tool that allows Congress to examine and scrutinize trade deals, including TPP.

TPA will require the administration to demonstrate that TPP meets over 150 congressionally-mandated trade objectives to protect American workers and our economy.

A congressional vote on the pact is not expected to occur until well into next year, providing the unions with the chance to maximize leverage with lawmakers coveting their support.

The president has to wait 90 days before signing the pact, and only then will Congress begin the process of voting on it.

Approval of the deal would give Obama a legacy-defining victory. To achieve a victory, Obama will need help from Republicans and will need to overcome doubts from a key Democratic constituency.

In the hours after the trade deal was announced, some union leaders also made clear that a 2016 presidential candidate's stance on the Trans-Pacific Partnership will determine whether he or she can expect support.

While unions have lost political clout as their numbers have declined, their political action committees donated more than $60 million to campaigns during the 2012 elections. About 90 percent of that money went toward Democratic candidates, according to the Center for Responsive Politics.

Chris Shelton, president of the Communications Workers of America, whose members include customer service reps and computer technicians, said the union will "hold accountable those members of Congress who support this giveaway to the 1 percent."

Among the Democratic candidates running for president, Sen. Bernie Sanders, I-Vt., moved quickly to voice his opposition.

"Wall Street and big corporations just won a big victory,” he tweeted.

Democratic frontrunner Hillary Clinton has yet to take a stance on the deal. The full text of the agreement is not yet available for public reading.

The TPP is designed to encourage trade among the United States, Australia, Brunei, Canada, Chile, Japan, Malaysia, Mexico, New Zealand, Peru, Singapore and Vietnam. The pact would reduce tariffs in the participating nations in a bid to open markets.

The White House said it will need support from both political parties for the deal to get support from Congress. It will have to overcome skepticism from Democrats in districts with deep manufacturing roots and from lawmakers representing states and districts where tobacco is grown. The agreement preserves the ability of participating countries to regulate tobacco and apply public health measures they consider most appropriate.

Members of the House Agriculture Committee have said they're concerned the deal won't do enough to improve access for rice farmers and the dairy industry.

"While I am encouraged to hear that U.S. livestock products such as beef and pork will see significant gains in market access, it will take a coalition of many to move TPP over the coming months," said committee Chairman Michael Conaway, R-Texas. "At this time, I am skeptical that these concerns were sufficiently addressed but will remain open-minded."

The Associated Press contributed to this report.