Southeast Asian stock markets fell on Monday, with Vietnam shedding nearly 3 percent and the Philippine index marking its lowest close in more than a year, as escalating U.S.-China trade tensions dampened sentiment.
U.S. President Donald Trump on Friday announced tariffs on $50 billion of Chinese imports, with a list of more than 800 strategically important imports from China that would be subject to a 25 percent tariff starting on July 6, prompting Beijing to immediately respond in kind.
Meanwhile, investors in Thailand and Philippines awaited policy meetings of the Bank of Thailand and Bangko Sentral ng Pilipinas due later in the week.
Vietnam shares closed 2.9 percent lower, after ending flat on Friday, as Petrovietnam Gas Joint Stock Corp slumped 6.2 percent and Vietnam Dairy Products JSC shed 4.1 percent.
Philippine shares ended 1.5 percent lower, their lowest close since April 2017. Financials and industrials weighed on the index with JG Summit Holdings Inc extending its decline for a third straight session and Bank of the Philippine Islands ending lower for a fifth straight session.
Thai shares extended losses to a fourth consecutive session, closing at their lowest level in nine months as energy stocks weighed on the index.
Oil prices fell on expectations that the Organization of the Petroleum Exporting Countries and its allies would increase supplies, and as China threatened duties on American crude imports.
Singapore shares marked their lowest close in eight months, dragged by financials. Heavyweight DBS Group Holdings Ltd and United Overseas Bank Ltd declined 1.3 percent and 1.9 percent, respectively.
The city-state's exports grew at the fastest pace in seven months in May, boosted by an extended surge in pharmaceutical shipments.
Indonesian financial markets are closed through Tuesday, June 19, for Eid Al-Fitr.