Singapore shares started the week in negative territory, pressured by rising oil prices amid ongoing uncertainty surrounding a potential truce between the U.S. and Iran in the Middle East.

The Straits Times Index fell 8.02 points, or 0.14%, to open at 5,703.09.

Market sentiment was dampened after U.S. President Donald Trump over the weekend reportedly rejected an Iranian proposal for a seven-day ceasefire and the reopening of the Strait of Hormuz to commercial shipping within a week.