The International Monetary Fund (IMF) has warned that Donald Trump’s implementation of sweeping new tariffs poses a “significant risk” to the global economy, as stock markets continue to be hit by a worldwide sell-off by investors, reports The Guardian.

Kristalina Georgieva, the managing director of the IMF, said it was important that the US and its trading partners avoided further escalating Trump’s trade war, while markets in Asia and Australia experienced further declines on Friday.

“We are still assessing the macroeconomic implications of the announced tariff measures, but they clearly represent a significant risk to the global outlook at a time of sluggish growth,” Georgieva said. “It is important to avoid steps that could further harm the world economy. We appeal to the United States and its trading partners to work constructively to resolve trade tensions and reduce uncertainty.”

The US president’s “liberation day” tariff policies, which have resulted in sweeping border taxes of between 10% and 50% imposed on almost every nation, wiped more than $2.5 trillion off Wall Street stocks and share prices in other financial centers across the globe on Thursday.

The sell-off continued into Friday, with Asian and European markets falling. Japan’s Nikkei index fell almost 3% on Friday, ending the week down 9%, while Tokyo’s Topix was down 4.5%. South Korea’s Kospi closed down 1.3%.

In London, the FTSE 100—which fell by 1.5% on Thursday in its worst day since last August—tumbled another 99 points, or 1.17%, to 8,375 points, the lowest since mid-January. Banking stocks were among the heavier fallers, with the Asia-focused Standard Chartered dropping by about 4%.