The Philippine Stock Exchange index (PSEi) fell 1.98 percent or 119.44 points to 5,899.18.
The drop came as ongoing geopolitical tensions weighed on sentiment and pushed the peso to a fresh all-time low.
“We expect geopolitical risks to continue acting as a headwind, while sustained inflation and global uncertainties are likely to keep financial conditions tight and limit upside potential in the near term,” said Wendy B. Estacio-Cruz, head of research at Unicapital Securities, in a text message on Monday.
Selling was broad-based, with mining and oil stocks leading declines as volatility in global energy markets intensified, data from the PSE showed.
But markets could rebound after signs of easing tensions between the US and Iran, though uncertainty may keep volatility elevated.
US President Donald Trump said on Monday that Washington and Tehran had held talks toward a “complete and total resolution of hostilities,” prompting him to postpone planned strikes on Iranian power plants.
Miguel R. Camus has been a reporter covering various domestic business topics since 2009.
