Twelve hours after China said it would retaliate against Mr. Trump’s next round of tariffs by raising taxes on American goods, Mr. Trump said he would bolster existing tariffs on $250 billion worth of Chinese goods to 30 percent from 25 percent on Oct. 1.
And he said the United States would tax an additional $300 billion worth of Chinese imports at a 15 percent rate, rather than the 10 percent he had initially planned. Those levies go into effect on Sept. 1.