"We know the value of imports and exports. American jobs depend on components coming from China," she said.

"Oakland is a unique port in that we are about half and half imports and exports, which is exactly why we see how interdependent we are, because we see the goods coming in from Asia into Oakland, the components that support the jobs at the Tesla factory right in our Bay Area," she noted.

Schaaf went on to say that the farm product that is grown in California, including the wine made in Napa, which is in the heart of the US famous Napa Valley, is being shipped out of the Oakland port to Asian markets.

China accounts for 37 percent of Oakland's total trade volume, including large quantities of US farm exports, according to Port of Oakland Executive Director Chris Lytle, who sent a letter in June to US Trade Representative Robert Lighthizer, warning that Trump's tariffs and China's counter-tariffs pose a major long-term threat to the economy.

"As a major seaport, we are extremely concerned by this trade war," Schaaf said, adding that "our president is harming our relations with China right now."

"We are globally interconnected. We benefit when we recognize how we can collaborate, not shut each other out," said the Oakland mayor.

She said the exchange of goods between the United States and China can make each other get stronger economically. "We all benefit when we have an exchange of goods and talent."