CANADA STOCKS-TSX drops to near three-week low as U.S. gov't stays shut

* TSX falls 103.88 points, or 0.81 percent, to 12,735.12

* All 10 main index sectors decline

* Suncor has biggest negative influence on index

* Takeover target BlackBerry drops 3.6 percent

* Valeant gains after drug, contact-lens approvals

By John Tilak

TORONTO, Oct 3 (Reuters) - Canada's main stock index dropped

on Thursday to its lowest in nearly three weeks as negative

sentiment caused by the extended U.S. government shutdown helped

offset upbeat economic data from China.

Every major sector on the index was trading in the red,

taking the Toronto market into negative territory for a second

straight session.

Investors also cast an eye on BlackBerry, which is

the focus of a $4.7 billion bid from a consortium led by Fairfax

Financial. Shares of the smartphone maker shed 3.6

percent.

Data showed rising demand caused activity in China's

services sector to expand at the fastest pace in six months in

September but failed to lift sentiment.

The focus of the market remained the U.S. government

shutdown, which dragged into a third day, highlighting the

political gridlock in Washington over the debt crisis.

"The market would suggest that they think this would

ultimately get resolved," said Paul Hand, managing director at

RBC Capital Markets. "But minute-by-minute people do feel

uncertainty."

The Toronto Stock Exchange's S&P/TSX composite index

closed down 103.88 points, or 0.81 percent, at

12,735.12, after reaching 12,700.02, its lowest since Sept. 13.

About 254 million shares changed hands on Thursday, compared

with an average daily volume of 304 million shares in September,

according to market operator TMX Group.

The TSX will likely make some gains and end the year around

13,400 as the U.S. debt woes ease and sentiment for Canadian

equities improves, Hand said.

All of the 10 main sectors on the index were in the red on

Thursday.

Shares of energy producers fell 1.1 percent, weighing the

most of any major sector.

Suncor Energy Inc lost 1.5 percent to C$36.25 and

had the biggest negative influence on the index. Canadian

Natural Resources Ltd gave back 1.4 percent to C$31.78.

The materials sector, which includes mining stocks, slipped

1.4 percent. Potash Corp was down 0.6 percent at

C$33.69, and Teck Resources Ltd declined 2 percent to

C$27.32.

BlackBerry slipped to C$7.97, taking the information

technology sector down 1.4 percent.

But Valeant Pharmaceuticals International Inc

climbed 1.4 percent to C$114.91 after the drugmaker won

regulatory approval for a topical nail fungus drug in Canada and

clearance for a new contact lens in the United States.