Singapore's non-oil domestic exports (NODX), a key gauge of the export performance of the economy, rose by 2.1 percent on-year in the second quarter of this year, trade promotion agency International Enterprise Singapore said on Tuesday.

The gain was significantly slower than the 4.8 percent growth in the previous quarter.

On a yearly basis, electronic exports grew slightly by 0.1 percent in the second quarter, after the 1.2 percent increase in the previous quarter. The increase was largely due to higher domestic exports of PCs, integrated circuits and telecommunications equipment, the agency said.

Non-electronic exports expanded by 2.9 percent, following the 6. 2 percent rise in the previous month, led by higher domestic exports of non-electric engines and motors, structures of ships and boats and specialized machinery.

For the second quarter, while NODX to Indonesia, China's Taiwan and Malaysia declined year-on-year, NODX to all the rest of the top markets increased. The biggest contributors to the expansion were the U.S., South Korea and Thailand.

NODX to the Chinese mainland rose by 0.5 percent in the second quarter on year, in contrast to the 5.6 percent contraction in the preceding quarter.

On a year-on-year basis, Singapore's total merchandise trade contracted by 10.6 percent in the second quarter, following a decline of 10.5 percent in the previous quarter. The decrease was attributed to the contraction in both oil trade and non-oil trade, which declined by 34.4 percent and 1.1 percent, respectively.

Looking ahead, the agency said that while the advanced economies are expected to see a gradual recovery, the growth outlook of regional economies has generally softened. Furthermore, the downward pressure in oil prices is expected to continue to depress oil trade further in nominal terms.

Taking all these into consideration, the agency has narrowed NODX growth forecasts for 2015 to between 1 and 2 percent.