* Tokyo rubber seen in 254-270 yen/kg range
* Sugar premiums seen stuck in 70-80 points range
* New harvest in Vietnam; cocoa butter ratios seen firm
By Lewa Pardomuan
SINGAPORE, Oct 7 (Reuters) - Bargain hunting and talk that China is building up rubber stockpiles again could push Tokyo futures up to resistance levels this week, while Thai sugar premiums may stay in their recent range as the crushing season approaches, dealers said on Monday.
The trend in other soft commodities may be dictated by demand prospects, with roasters expected to wait for robusta premiums to slip due to an abundant crop in top producer Vietnam. Cocoa butter premiums, however, could stay at their highest in five years.
The most active March rubber contract on the Tokyo Commodity Exchange rose about 1.3 percent to a high of 257.50 yen a kg after losing nearly 6 percent in thin trade last week as markets in China were closed for a holiday. Trading resumes there on Tuesday.
Key support was pegged at 254 yen a kg and resistance at 270 yen. The Tokyo market, which sets the tone for tyre-grade prices, often tracks movements in equities and currencies.
"Tokyo rubber has gone down too much. I think it may go back to 265 yen today or tomorrow," said Gu Jiong, an analyst at Yutaka Shoji Co in Tokyo.
"I've heard the (Chinese) government may buy a total of 200,000 tonnes of rubber; 150,000 will be from the local market and 50,000 tonnes from the foreign market. It may support the price."
Last year, China announced it would buy up to 200,000 tonnes of rubber from the domestic market to support prices but dealers said only a fraction was purchased by the end of 2012.
In the sugar market, Thai high polarisation, or hipol, raws were unchanged at 70 to 80 points over New York futures even though the sweetener was sold at higher premiums at a government tender last week.
The state-run Thai Cane and Sugar Corp (TCSC) sold 122,000 tonnes of raw sugar from the 2013/14 crop to international trading houses at premiums ranging from 88 to 105 points.
This week's early indications suggest buyers are waiting for lower differentials as fresh supply from Thailand is expected to enter the physical market in the next few weeks.
"There is no change in premiums despite the higher levels shown in last week's tender," said a dealer in Bangkok.
Thai sugar production is forecast to reach 11 million tonnes in 2013/14, raising the prospect of higher exports. The 2013/14 crushing season is due to start on Nov. 15 and will run until late April.
Cocoa butter, a key ingredient of chocolate, could stay around the highest ratios since 2008 this week as chocolate makers chase cargoes for delivery this year.
Jean-Marc Anga, executive director of the International Cocoa Organization, told Reuters on Monday the global cocoa market would be in deficit for the next four years, underscoring the impact of rising consumption in Asia and supply problems.
In the coffee market, premiums for Vietnamese robustas could drop from last week's levels of $10 to $20 to London futures as dealers expect more offers.
The new season in Vietnam started this month and the 2013/14 crop could hit a record 25 million 60-kg bags in the period to September 2014, a Reuters poll showed. (Editing by Alan Raybould)