* Pro-Russian separatists claim victory in Ukraine vote
* Dollar surrenders ground versus euro; index down 0.1 pct
* Chinese premiums at $3/oz, demand still seen as soft
(Updates throughout, changes dateline, pvs SINGAPORE)
LONDON, May 12 (Reuters) - Gold rose above $1,290 an ounce on Monday as simmering tensions in Ukraine and a weaker dollar lent support, but a lack of investment on the back of expectations for strengthening U.S. growth held gains in check.
Pro-Russian rebels declared a landslide victory in Sunday's referendum in Ukraine's Donetsk and Luhansk regions. The Ukrainian authorities dismissed the vote as a farce, and the European Union criticised the referendum.
A stand-off between Russia and the West over Ukraine has helped lift gold prices from April's 2-1/2 month lows, but the metal has struggled to extend gains above $1,300 an ounce.
Spot gold was up 0.4 percent at $1,294.16 an ounce at 0952 GMT, while U.S. gold futures for June delivery were up $6.80 an ounce at $1,294.40.
"We have held around $1,300 an ounce for the last month and a half, and gold needs something to shake it out of that," Mitsui Precious Metals analyst David Jollie said.
"What could drive that? Geopolitical issues are likely to be a major driver. A change in U.S. and European attitudes towards sanctions in Russia could ratchet up interest in gold, as could more problems in eastern Ukraine," he said.
"(But) the current situation in Ukraine is already in the price. It would take a change in that to move things from here."
The metal has held within a narrow range for the past three sessions, with prices firmly supported at the 100-day simple moving average level at $1,288 an ounce. An early dip to a one-week low at $1,279 an ounce was quickly reversed.
Gold has taken support from a softer dollar, with the U.S. unit surrendering on Monday some of the gains it made last week against the euro after the European Central Bank indicated it was comfortable with easing monetary policy in June.
It remains under pressure, however, from expectations that better prospects for the U.S. economy will prompt the Federal Reserve to keep scaling back the gold-friendly monetary stimulus measures it put in place after the financial crisis.
"Fed Chairwoman (Janet) Yellen's Congressional testimony on Wednesday led to mounting speculation that the U.S. will continue to trim monetary stimulus measures this year - gold predictably sold off," Mitsubishi analyst Jonathan Butler said in a note on Monday.
GOLD BUYING SUBDUED
Meanwhile, subdued buying in the physical markets is also hurting sentiment towards gold.
In top buyer China, local premiums over the global benchmark have climbed to about $3 an ounce after trading at a discount for most of the last two months on weak demand.
But they are still much lower than the over-$20 premiums seen earlier in the year.
"China's weakening demand for physical metals was once again confirmed by concrete figures (last week), especially investment demand: according to the China Gold Association demand for gold bars fell in the first quarter by 44 percent compared to the same period last year," Swiss precious metals house Heraeus said in a note.
Among other precious metals, silver was up 1.9 percent at $19.47 an ounce, spot platinum was up 0.7 percent at $1,431.75 an ounce and spot palladium was up 0.8 percent at $803.70 an ounce.
Platinum miner Lonmin said on Monday that restructuring and job cuts were inevitable as it posted a steep fall in six-month earnings, suffering from South Africa's longest and most costly labour stoppage.
The pay dispute in the world's top platinum producing country has cut 40 percent of global production and halted operations at Lonmin's mines and processing plants.
(Additional reporting by A. Ananthalakshmi in Singapore; editing by Jane Baird)