President Trump’s move fulfills a major goal of the chipmaker. But the move faces opposition in Washington — and uncertainty in Beijing.

Anthropic, the artificial intelligence start-up, said that Chinese state-sponsored hackers used its tools in a widespread attack.

The highly anticipated event covered a lot of ground on tariff and trade barriers, but questions remain about reaching a lasting accord.

Investors sent major global indexes higher on optimism that President Trump and China’s top leader, Xi Jinping, could reach a wider agreement this week.