* Dollar index slips to lowest since Dec. 1
* Australian dollar and Canadian dollar hit 2-month highs
* Bitcoin slides more than 10 pct at one point (Updates levels)
By Masayuki Kitano
SINGAPORE, Dec 28 (Reuters) - The dollar slid broadly on Thursday, hampered by a recent dip in U.S. 10-year bond yields, while commodity-linked currencies were bolstered by this week's rally in metals and oil prices.
In the cryptocurrency market, bitcoin came under renewed pressure, tumbling by as much as 10.8 percent on the Luxembourg-based Bitstamp exchange.
The dollar's index against a basket of six major currencies slipped to as low as 92.734 .DXY , its weakest level in almost four weeks.
The index has dropped more than 9 percent this year, putting it on track for its biggest annual slide since 2003.
"Bond yields have pulled back from their peaks and the dollar is trading with a soft tone," said Satoshi Okagawa, senior global markets analyst at Sumitomo Mitsui Banking Corporation in Singapore, referring to a pullback in U.S. 10-year Treasury yields.
The U.S. 10-year Treasury yield stood at 2.425 percent US10YT=RR on Thursday, having come off a nine-month high of 2.504 percent set last week.
The euro rose 0.4 percent to $1.1929 EUR= . The single currency has gained more than 13 percent so far this year, well on the way for its best annual performance since 2003.
Against the yen, the dollar slid 0.5 percent to 112.78 yen JPY= .
This week's drop in the dollar probably partly reflects a sell-the-fact type of reaction after U.S. President Donald Trump signed U.S. tax reforms into law last week, said Lee Jin Yang, macro research analyst for Aberdeen Standard Investments in Singapore.
"I think people have been long dollars into the (Fed's December) rate hike, into the passage of the tax bill, and right now people are just pulling back," Lee said, referring to short-term market positioning.
Currencies of commodities exporters remained firm, in the wake of this week's rise in oil prices LCOc1 to 2-1/2 year highs and a surge in copper prices CMCU3 to four-year peaks.
The Australian dollar touched a two-month high of $0.7799 AUD=D3 on Thursday, having gained more than 1 percent so far this week.
The Canadian dollar CAD=D3 also touched a two-month peak of C$1.2613 per U.S. dollar.
Bitcoin, the biggest and best-known digital currency, was last down 8.9 percent on the day at around $14,000 BTC=BTSP on the Luxembourg-based Bitstamp exchange.
Earlier on Thursday, South Korea's government said it will impose additional measures to regulate speculation in cryptocurrency trading in the nation, where bitcoin has drawn wide participation from housewives and students.