VOLATILE factory output data and trade tensions between the world's two biggest economies weighed on Singapore on Monday, despite reports that the United States and China have opened talks on tariffs.

The benchmark Straits Times Index (STI) lost ground for the fourth straight day, dipping by 8.93 points, or 0.26 per cent, to 3,412.46.

It had started the day on soft footing, then rallied after the lunch break to an intra-day high of 3,429.75 around 3.20pm. But a selloff in the last hour or so of trading eroded and then erased those gains.