SINGAPORE - A lacklustre showing in the manufacturing sector dragged down economic growth in the second quarter of this year, which came in at just 1.7 per cent, the slowest since the third quarter of 2012.

This was significantly slower than the 2.6 per cent tipped by economists in a Bloomberg poll, and also lower than the 2.8 per cent logged in the first three months of the year.

The figure is also much weaker than the 2.7 per cent prediction in a quarterly survey of economists by the Monetary Authority of Singapore (MAS) released in June.

Advance estimates released on Tuesday by the Ministry of Trade and Industry (MTI) showed the manufacturing sector contracted by 4 per cent over the same quarter last year.

This was the sector's third consecutive month of declining output. The contraction was largely due to a fall in output in the biomedical manufacturing and transport engineering clusters.

The construction sector expanded 2.7 per cent, supported by strong growth in public sector building activities. This was up from the preceding quarter's 2.1 per cent growth.

Services producing industries grew 3 per cent, slower than the 4.2 per cent logged in the first three months of the year. This was largely due to slower expansion in the wholesale and retail trade and business services sectors, as well as a contraction in the transportation and storage sector.

On a quarter-on-quarter seasonally-adjusted annualised basis, the economy contracted by 4.6 per cent, a reversal from the 4.2 per cent expansion in the preceding quarter, MTI said.

The Singapore dollar dropped after the data, with the US dollar fetching 1.3601 Singollars, the weakest since June.

Economists have been lowering their forecasts for Singapore's economic growth in the April-June quarter, saying sluggish global demand has hurt the manufacturing sector.

The Government has maintained its full-year GDP growth forecast at between 2 and 4 per cent in 2015.