* TSX down 116.95 points, or 0.91 percent, at 12,803.19
* Eight of the TSX's 10 main groups move lower
TORONTO, Jan 6 (Reuters) - Canada's benchmark stock index fell on Wednesday as energy stocks slid and heavyweight banks and railways pulled back amid rising geopolitical tensions and growth worries.
The most influential movers included pipeline company Enbridge Inc, which fell 2.1 percent to C$45.03, and Suncor Energy Inc, the country's largest oil and gas company, which declined 2.4 percent to C$34.56.
The energy group overall retreated 2.8 percent, with oil prices sliding over 4 percent to fresh 11-year lows as tensions between Saudi Arabia and Iran made any cooperation between them to cut output even more unlikely.
The index's financials group retreated 0.9 percent, with Bank of Nova Scotia off 1.1 percent to C$55.52.
At 10:40 a.m. EST (1540 GMT), the Toronto Stock Exchange's S&P/TSX composite index was down 116.95 points, or 0.91 percent, at 12,803.19. Of the index's 10 main industry groupings, only two were in positive territory.
"I think that everybody is just sitting and watching and waiting to see if something will stabilize," said Diana Avigdor, a portfolio manager and head of trading at Barometer Capital Management. "From a trading perspective, there's just no bids anywhere."
If sustained, the decline would mark the index's sixth straight losing session.
On the positive side, Valeant Pharmaceuticals International Inc rose 2.4 percent to C$144.6 after naming an interim CEO. Gold miners also rose, including Goldcorp, which advanced 4.2 percent to C$16.88 and Barrick, which jumped 4.1 percent to C$11.14.
The overall materials group, which includes miners, climbed 1.3 percent as the price of bullion hit a four-week high.
Gold futures rose 1.1 percent to $1,090.5 an ounce, while U.S. crude prices were down 3.3 percent to $34.77 a barrel and Brent lost 4.3 percent to $34.86.
Canada's exports grew for the first time in four months in November, helping cut the trade deficit to C$1.99 billion ($1.41 billion) from C$2.49 billion in October, Statistics Canada said.
Automakers sold fewer light vehicles in Canada during December, but reported record-breaking sales of trucks and cars for 2015, an automotive consultant said on Tuesday.
Declining issues outnumbered advancers ones on the TSX by 175 to 59, for a 2.97-to-1 ratio on the downside. (Reporting by Alastair Sharp and Fergal Smith, editing by G Crosse)