Singapore shares incurred losses on Tuesday, mirroring regional losses as investors responded negatively to the possibility of the US and Iran returning to hostilities amid a fragile ceasefire.

The Straits Times Index (STI), a key benchmark for the Singapore Exchange, ranged between 4,891.83 and 4,920.61 throughout the day. It ended the session at 4,920.61, down 3.70 points or 0.1% compared to Monday's close.

In economic news, Singapore's total retail sales rose 4.8% year on year in March, following the 8.3% growth in the preceding month, according to data released by the Department of Statistics Singapore.

On the corporate front, shares of UltraGreen.ai (SGX:ULG) dropped over 7% at the close as its total vial shipment fell 8.7% during the first quarter of the year to 280,900 vials from 307,600 vials a year earlier.

Overseas-Chinese Banking Corp. or OCBC (SGX:O39) were hardly moved at the close, as it agreed to acquire the retail and wealth management business of HSBC's (HKG:0005) Indonesian arm.

Meanwhile, shares of United Overseas Insurance (SGX:U13) were down under 1% as its insurance revenue dropped to SG$24.9 million in the first quarter of the year from SG$27.3 million a year earlier.

STI down 0.1%; SingPost, Golden Agri-Res up 6%; Seatrium up 3%; Olam, Sheng Siong up 2%; OUE down 3%; YZJ Shipbldg down 2%.