WASHINGTON/BEIJING (Reuters) – U.S. President Donald Trump’s escalation of a trade war with China left plans in limbo on Monday for high-level negotiations later this week to end the dispute.

Stocks around the world tumbled and oil prices hit a one-month low after Trump tweeted on Sunday that he would raise tariffs on $200 billion worth of Chinese goods to 25 percent from 10 percent by the end of the week, and would “soon” target the remaining Chinese imports with tariffs.

The announcement ended a four-month truce in a trade war that has cost the world’s two largest economies billions of dollars, slowed global growth and disrupted manufacturing and farming.

It was unclear on Monday whether Chinese Vice Premier Liu He would travel as planned