* Technical signals for gold seen as positive-analyst
* Silver ETF holdings edge up to highest since September
* GRAPHIC-2017 asset returns: http://tmsnrt.rs/2jvdmXl (Updates prices, market comment; adds byline, NEW YORK dateline)
By Chris Prentice and Jan Harvey
NEW YORK/LONDON, Dec 28 (Reuters) - Gold extended gains on Thursday to a one-month high on a strong technical outlook and a U.S. dollar at a four-week low, as palladium prices reversed earlier losses to touch a fresh 17-year high.
The metal benefited from technically driven momentum after closing above its 100-day moving average on Wednesday for the first time since late November, analysts said.
Spot gold XAU= was up 0.59 percent at $1,294.58 per ounce by 2:37 p.m. (1937 GMT) after hitting its highest since Nov. 29 at $1,295.21 an ounce. U.S. gold futures GCv1 for February delivery settled up 0.45 percent at $1,297.20 per ounce.
Higher lows have bullion's chart looking strong, said Eli Tesfaye, senior market strategist for brokerage RJO Futures in Chicago.
"The technicals favor the upside. The gravitational force is trying to break through the (key) psychological level of $1,300," he said.
Continued softness in the dollar bolstered bullion, with additional strength lent by commodities markets including copper and crude oil, traders said. Brent crude oil futures LCOc1 stayed near 2-1/2-year highs and copper CMCU3 touched a four-year peak. dollar retreated against a basket of currencies, with the index .DXY slipping to its lowest since late November on a less certain U.S. economic outlook after the passage of major tax cuts. weakness in the dollar is playing its part," Naeem Aslam, chief market analyst at ThinkMarkets, said. "We do think that this trend will continue into 2018. We expect the gold price to finish the year above $1,300 mark, and that would send a strong buy signal for traders."
The dollar index is down more than 9 percent so far this year, set for its biggest annual loss since 2003. That's helped lift gold nearly 5 percent from a near five-month low of $1,235.92 struck in mid-December.
"With the Relative Strength Index (RSI) still at neutral levels, the technical picture suggests there is still potential topside in this rally," currency broker OANDA said in a note.
Net gold imports to major consumer China via main conduit Hong Kong fell 23.6 percent in November from the previous month, data showed. XPD= touched its highest since February 2001 at $1,072 and 0.80 percent at $1,069, continuing its climb on expectations of short supplies and strong demand.
Silver XAG= was up 0.88 percent at $16.83 an ounce after hitting a one-month high of $16.887. Holdings of silver exchange-traded funds tracked by Reuters rose to their highest since early September, with Thursday's data showing a 62-tonne inflow.
Platinum XPT= was up 0.49 percent at $921.50 an ounce.