Singapore shares opened the week with losses on Monday, as investors cautiously monitored geopolitical developments following U.S. President Donald Trump's statement that he canceled planned strikes on Iran.

The Straits Times Index was down 0.43%, or 24.42 points, to open at 5,604.080.

Trump said negotiations with Iran will resume on Monday following his declaration that he was canceling a planned attack, provided a deal to end the months-long conflict is reached "rapidly".

However, market sentiment remained subdued, as U.S.-Iran diplomatic talks have remained fragile since a prior ceasefire agreement collapsed.