* Thai sugar premiums to be in current ranges amid ample global supply
* Supply dictates Vietnam coffee premiums
* Tokyo rubber may test resistance of 290 yen/kg
By Lewa Pardomuan
SINGAPORE, Dec 16 (Reuters) - Thai raw sugar premiums could be stuck in a range this week amid ample global supply, while benchmark Tokyo rubber futures may touch a key resistance level because of a weaker Japanese currency, dealers said on Monday.
In robustas, dealers will keep track on supply from main producers Vietnam and Indonesia, while trading could slow to a trickle in the cocoa-butter market as chocolate makers wind down ahead of year-end holidays.
Early indications showed Thai Jan-March high-polarisation, or hipol, raw sugar stood at premiums of 65 to 75 points to New York futures, unchanged from last week, despite a tumbling global market.
Premiums usually rise when New York futures drop, but abundant supply in Asia and South America have prevented sellers from pushing up the values. Crushing has started in Thailand after a slight delay and top consumer India is selling excess sugar.
"There's no shortage of sugar floating around the market," said Luke Mathews, a commodities strategist at Commonwealth Bank of Australia. "At the moment, the overwhelming sentiment within the sugar pit is bearish."
ICE March sugar futures eased 0.03 cents to settle at 16.27 cents a lb on Friday, having earlier fallen to 16.22 cents, the weakest level since late July.
London robustas defied the odds, with second-month March rising to $1,813 a tonne on Friday, their highest level since late August, as falling exchange-certified stocks spurred fears of nearby supply tightness.
Vietnam's robusta coffee could stay at premiums of $20 to London futures as farmers hold back stocks, but Indonesian differentials have dropped more than $100 to around $30 because of pressure from rising London futures.
Last December, Vietnamese beans traded below London futures.
"Robusta is supported by Vietnam and certified stocks have also fallen. But after all, the harvest in Vietnam is still expected to be a record," said Vanessa Tan, an investment analyst at Phillip Futures. "If you look at the fundamentals, then the supply is there. The uptrend could reverse anytime."
In the rubber market, the most active May contract on Tokyo Commodity Exchange could test 290 yen this week, but gains could be capped by high inventory. The contract hit a high of 287.9 yen a kg on Monday, its strongest since Sept. 9, before easing slightly as speculators booked profits.
"I don't think we've got strong fundamental support from the physical market," said Gu Jiong, an analyst at Yutaka Shoji Co. "If the price goes to 290 yen, I think the funds will continue to take profits."
Crude rubber inventories at Japanese ports stood at 9,320 tonnes as of Nov. 20, rising 30 percent from 10 days earlier. That marks the highest since 10,192 tonnes on July 20. (Editing by Muralikumar Anantharaman)