Most Southeast Asian markets fell on Friday after US President Donald Trump vowed to levy 10% tariff on remaining $300 billion worth of Chinese goods, sparking fears of an escalation in the prolonged trade row.
September onwards, nearly all of China's exports to the United States will be taxed, which "significantly raises the intensity of the trade war with negative implications for world growth, global manufacturing and business investment," Westpac said in note.
Singapore stocks, counted among the most sensitive to trade war developments, declined nearly 1% to lead losses in Southeast Asia.
The index lost 3.1% during the week.
Thai shares tumbled to their worst session in four months after an overnight plunge in oil prices battered energy stocks.
For the week, the benchmark lost 2%.
Malaysia's main index followed suit to close at its lowest in two months after June exports defied market expectations to slip by 3.1%.
Telco Maxis Bhd was the biggest drag on the index as it slumped 4.9% on reporting a steep drop in its quarterly net profit.
The Malaysian benchmark fell 1.3% this week and logged its fourth straight weekly loss.
Bucking the regional trend, Philippines added 0.4% after sliding as much as 1.1% in the session, with consumer stocks dominating the benchmark. But, the index closed 0.7% lower for the week.