U.S. Treasury Secretary Steven Mnuchin walks to a working breakfast at the G-7 Summit in Biarritz, France on Aug. 25, 2019. Erin Schaff | AFP | Getty Images

SAINT-JEAN-DE-LUZ, France — American Treasury Secretary Steven Mnuchin doubled down on the White House's latest punch in the U.S.-China trade war by calling out Beijing for unfair trade practices. "We do not have free trade with them," Mnuchin said Sunday on the sidelines of the G-7 meeting in France. "It's a one way street: They have free entrance into our markets, our investments, our companies and we do not have the same thing there. That's the only reason why we are in this situation with China. If China would agree to a fair and balanced relationship, we would sign that deal in a second," he added. "Sometimes you've got to take stern measures," White House economic advisor Larry Kudlow said alongside Mnuchin, adding that American companies should heed the president's call to leave China.

"Come home to America, we've got the best tax system, we've got the best regulatory system, it's an easy place to make money, the best technology in the world. Come home. That's what the president is saying," Kudlow said. Before leaving for the G-7, President Donald Trump said he would raise existing duties on $250 billion in Chinese products to 30% from 25% on Oct. 1. Additionally, he said, tariffs on another $300 billion of Chinese goods, which start to take effect on Sept. 1, will now be 15% instead of 10%. At the G-7, Trump said Sunday he could declare the escalating U.S.-China trade war as a national emergency if he wanted to. "In many ways this is an emergency," Trump said of the ongoing trade battle. "I could declare a national emergency, I think when they steal and take out and intellectual property theft anywhere from $300 billion to $500 billion a year and when we have a total lost of almost a trillion dollars a year for many years," Trump said, adding that he had no plan right now to call for a national emergency.

U.S. President Donald Trump attends a bilateral meeting with Britain's Prime Minister Boris Johnson during the G7 summit on August 25, 2019 in Biarritz, France. Pool | Getty Images News | Getty Images