WASHINGTON (Reuters) - U.S. President Barack Obama is fully committed to pushing for Congress to ratify the Trans-Pacific Partnership (TPP) deal despite anti-trade sentiment gaining steam on the presidential election campaign trail, National Security Adviser Susan Rice said on Wednesday.

U.S. National Security Advisor Susan Rice (C) joins President Barack Obama as he participates in a bilateral meeting at the State House in Nairobi, in this July 25, 2015 file photo. REUTERS/Jonathan Ernst/Files

Voter anxiety and anger over international trade and the 12-nation Pacific trade pact have helped propel the campaign of Donald Trump, the Republican front-runner, as well as Senator Bernie Sanders, who is running against Hillary Clinton for the Democratic nomination.

“The president remains fully committed to working to achieve ratification on the U.S. side and encouraging all of our TPP partners to move through their domestic processes to do the same,” Rice told Reuters in an interview on Wednesday.

For Obama, the TPP is a legacy issue, and standing firm on the pact reassures other nations with high expectations for the deal. At the same time, it highlights a division with Clinton, a close political ally, who has been grappling with Democratic anxiety about trade on the campaign trail.

Obama’s commitment to the trade deal means that it will likely remain a hot campaign issue and exposes Clinton to trade-bashing rhetoric ahead of the Nov. 8 vote to elect Obama’s successor.

Sanders has accused Clinton of backing “disastrous” trade policies that moved manufacturing jobs overseas, and questioned the sincerity of her opposition to the TPP since she became a presidential candidate.

Clinton had supported the trade pact when she was secretary of state during Obama’s first term, but later said she was worried the deal would not do enough to crack down on currency manipulation or protect consumers from excessively high drug prices.

Sanders’ unexpected victory in the Democratic primary in Michigan on Tuesday suggests that his criticism is resonating with some voters, and could spell trouble ahead for Clinton in states such as Ohio, Wisconsin and Pennsylvania.

Trump’s anti-free trade rhetoric and promise to slap taxes on cars and parts shipped in from Mexico have also found support among Republican voters, helping him score a big victory in the party’ primary in Michigan on Tuesday.

“There have been times - and this is one of them - where anti-trade sentiment has attained some salience in our domestic politics as well as in other countries,” Rice said.

“There’s been an evolution over the decades in the nature of trade agreements and in the caliber of trade agreements. And I’m not sure that that has fully been absorbed in the public mindset or the political discourse,” she said.

Obama has repeatedly said that the TPP will expand markets for U.S. exporters and has high standards on labor and the environment that were not part of the North American Free Trade Agreement with Canada and Mexico.

Rice said policy makers face the challenge of being able to articulate the benefits of TPP and “to not allow the sort of traditional ‘old saws’ of the critical narrative about trade to go unchallenged, when to a considerable extent they’re based on agreements of the past.”

Rice made her comments ahead of a summit between Obama and Prime Minister Justin Trudeau of Canada, a nation also wrestling with the merits of the TPP. The economy of Canada, the largest market for U.S. exports, is heavily reliant on open trade with the United States.