SINGAPORE (Reuters) - Singapore shares lingered near their lowest level in more than three weeks, awaiting cues on China's economic agenda from a key four-day Communist Party policy meeting.

The benchmark Straits Times Index was nearly flat at 3,186.95 at 1.30pm local time, in line with a 0.1 per cent fall in the MSCI's broadest index of Asia-Pacific shares outside Japan.

China's leaders will unveil a reform agenda for the next decade later on Tuesday, seeking to balance the need to overhaul the world's second-largest economy as it loses steam with preserving stability and to reinforce the Communist Party's power.

Shares of Sembcorp Industries dropped 0.4 per cent to $5.30, with trading volume exceeding its 30-day average, after the company posted margins below expectations, despite a 9 percent increase in net profit in the first nine months from a year earlier.

"We see limited near-term share price upside with lingering concerns over power prices in Singapore amid intense competition," Maybank Kim Eng wrote in a research note.

Sembcorp's overseas operations could post positive earnings surprise, but long-term prospects would depend on the pipeline of utilities project," Maybank said.

Maybank has a "hold" rating on the stock and maintains its target price of $5.50.

Commodities firm Noble Group and property developer City Developments were up 1.4 per cent and 0.8 per cent respectively, ahead of their earnings to be released on Tuesday after market hours.