Singapore shares closed 1.02 percent lower on Wednesday, weighed by economic uncertainty in China and the U.S. as well as political tensions in Ukraine. Investors are waiting for Chinese data on industrial output, retail sales and urban investment due on Thursday, which might offer some clarity on where the world's second-largest economy is heading. The standoff in Ukraine is also a concern for investors. On Tuesday, Ukraine's acting president announced the formation of a volunteer national guard, while ousted leader Viktor Yanukovich insisted that he remained the legitimate leader. The benchmark Straits Times Index dropped 31.97 points to close at 3,097.43 points. Trading volume was 2.04 billion shares worth 1. 13 billion Singapore dollars. Decliners outnumbered advancers 261 to 179, while 513 stocks closed unchanged. Phillip Securities Research said "an upward break of resistance zone starting at 3,120 points and 3,150 points implies further short term upside." CIMB Research said failing to move above 3,190 points will bring about another bout of selling, which could send prices back down to retest 2,990 points and 3,025 points. Among top actives, JES International Holdings rose 1.4 percent to 14.8 Singapore cents. It has secured contract plus options worth up to 120 million U.S. dollars, continuing on its recent contract win momentum in 2014. The latest contract win is for the construction of a Post-Panamax bulk carrier plus the options for another 3 similar vessels. Vard Holdings gained 4.4 percent to 94 Singapore cents. It announced that it has signed a Letter of Intent with repeat Norwegian customer Solstad Offshore for the design and construction of an advanced Offshore Subsea Construction Vessel ( OSCV) for delivery in second quarter of 2016. The OSCV is not only anticipated to be the largest vessel in the Solstad fleet on delivery, but will also be the largest ever constructed by Vard. Sembcorp Marine shed 0.5 percent to 3.98 Singapore dollars. Its wholly owned Sembawang Shipyard has signed an agreement with RCL Cruises Limited, a member of the Royal Caribbean Cruises, to perform the extensive revitalization of Royal Caribbean International's passenger-ship Voyager of the Seas. Among the top gainers, Dairy Farm International rose 2.7 percent to 9.37 U.S. dollars, while Jardine Matheson became one of the top losers by falling 1.6 percent to 59.04 U.S. dollars. (1 U. S. dollar equals to 1.27 Singapore dollars).