Singapore shares started the week positively despite a backdrop of diplomatic friction, as U.S. President Donald Trump dismissed recent Iranian remarks regarding regional stability as "totally unacceptable."

The Straits Times Index (STI), a key benchmark for the Singapore Exchange, ranged between 4,908.76 and 4,956.77 throughout the day. It ended the session at 4,942.77, up 20.87 points or 0.42% compared to Friday's close.

On the corporate front, shares of Geo Energy Resources (SGX:RE4) closed over 3% higher as it signed a term sheet with Swiss private commodities investment company, Resource Invest under which the latter will invest directly or indirectly around $1.5 billion in the company's Indonesian subsidiary, Marga Bara Jaya.

BRC Asia's (SGX:BEC) shares closed nearly 3% lower as its attributable profit to owners rose 24% in the fiscal first half ended March 31, to SG$52.0 million from SG$42.1 million a year earlier.

Meanwhile, shares of Autago (SGX:WNH) surged over 33% at the close as it completed its share consolidation exercise on May 8.