* KOSPI down 0.2 pct at 1,940.70 points
* Automakers up as Hyundai Motor union agrees to resume work
* Chemicals lose ground as OCI says Suntech orders cancelled
By Hyunjoo Jin
SEOUL, April 29 (Reuters) - South Korean shares ended slightly lower on Monday as weaker-than-expected U.S. gross domestic product data fuelled concerns that one of the country's key export markets was losing momentum.
The Korea Composite Stock Price Index (KOSPI) finished down 0.2 percent at 1,940.70 points.
"I have a conservative view of the global economy in the current quarter, and with South Korea's stimulus struggling to gain traction here, South Korean companies will suffer at home and abroad," said Park Hyeong-joong, an analyst at Meritz Securities.
Automakers bucked the trend, however, after Hyundai Motor's labour union agreed to restart weekend production from this week following output stoppages in March and April that hit sales and earnings.
Hyundai gained 1.6 percent, while Kia Motors rose 3 percent.
"There are expectations that automakers' profitability would improve in the second quarter, with increased domestic production and utilization rates," said Jang Moon-soo, an analyst at Eugene Investment & Securities.
OCI ended down 2.1 percent after the chemicals firm said on Friday that three polysilicon orders worth 1.46 trillion Korean won ($1.31 billion) from units of China's solar panel maker Suntech Power Holdings Co Ltd were cancelled because of the latter's financial troubles.
Shipbuilders and shipping firms were among the worst performers, with STX Offshore & Shipbuilding down 5.6 percent and Hyundai Merchant Marine falling 5.6 percent.
Telecom firms, seen as defensive stocks, gained ground, with LG Uplus up 4.2 percent and SK Telecom gaining 2.6 percent.
Move on day -0.2 percent
12-month high 2,031.10 2 January 2013
12-month low 1,769.31 25 July 2012
Change on yr -2.8 percent
All-time high 2,231.47 27 April 2011
All-time low 93.10 6 January 1981 (Reporting by Hyunjoo Jin; Editing by Kim Coghill)