SAN FRANCISCO — California Sen. Kamala Harris attacked President Trump's tariffs against China as a "trade tax" against average Americans during her remarks at the California Democratic Party convention.

While listing a number of alleged broken campaign promises by Trump, Harris aimed her sights on the growing tensions and tariffs between the U.S. and China, which are currently in the middle of trade negations.

"Remember how he said he'd bring back those good jobs?" Harris told a packed convention center Saturday morning. " But what'd he do? He turned around and started a trade war. And let's call it what it is: It's a trade tax. I'd like to call it Trump's trade tax, and this trade tax is taking $1.4 billion out of working people's pockets every month."

Harris's attack on Trump's trade war breaks with Senate Democratic Minority Leader Chuck Schumer, who offered support to the president at the beginning of May.

"Hang tough on China, President @realDonaldTrump. Don’t back down. Strength is the only way to win with China," Schumer tweeted.

On Friday, Trump announced plans for tariffs against Mexico in response to illegal border crossings.

“On June 10th, the United States will impose a 5% Tariff on all goods coming into our Country from Mexico, until such time as illegal migrants coming through Mexico, and into our Country, STOP,” he wrote on Twitter. “The Tariff will gradually increase until the Illegal Immigration problem is remedied.”