Now that U.S. President Joe Biden has signed off on a law that could expel TikTok from the U.S. market, Beijing must decide how best to retaliate over an attack on the world’s most-valuable start-up.

The legislation approved on Wednesday would give Chinese parent company ByteDance nearly a year to divest the video-sharing platform before facing an outright ban. At a daily briefing hours before, China’s Foreign Ministry directed reporters to a vow by commerce officials last month to take "measures to resolutely safeguard its legitimate rights and interests.”

Chinese President Xi Jinping’s government has so far shown restraint in responding to a drumbeat of U.S. trade curbs during a hawkish election season. The Communist Party’s moderation has been made easier by Biden’s choice of largely symbolic actions, such as tariffs on metals China exports little of to America.