China's Shanghai Composite lost 0.5% to 2,884.54 after surveys showed a deteriorating manufacturing outlook in May. Japan's Nikkei 225 index lost 1.3% by midday to 20,343.52, and Hong Kong's Hang Seng shed 0.4% at 26,807.91. The S&P ASX 200 dropped 0.9% to 6,340.90.
A private survey, the Caixin manufacturing purchasing managers' index, or PMI, held steady at 50.2 in May. But business confidence slipped to the lowest level since the series began in April 2012. The official manufacturing PMI, issued Friday, sank to one of the lowest levels in three years. Meanwhile in Singapore, China's defence minister warned its military would "resolutely take action" to defend Beijing's claims over self-ruled Taiwan and disputed areas of the South China Sea.
"Let's understand that trade conflicts are the catalyst for the real issue; slower global growth leading to stagflation and recessionary conditions," Chris Weston of Pepperstone said in a commentary. "With the weekend news flow centring again on trade, where a Chinese white paper attributed the blame on relations to Trump, amid Chinese authorities investigating FedEx, it all suggests things will only get worse before they get better.
The move spurred a broad sell-off that sliced more than 350 points from the Dow Jones Industrial Average, which closed down 1.4% at 24,815.04. The selling left the benchmark S&P 500 index 6.6% lower for the month as it lost 1.3% to 2,752.06.The Nasdaq slid 1.5% to 7,453.15. The Russell 2000 index of smaller companies gave up 1.4% to 1,465.49.