*

TSX ends down 0.1%, at 25,119.71

*

Energy falls 0.7%; oil settles 0.9% lower

*

Air Canada shares tumble 9.4%

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Annual inflation rate slows to 1.9%

(Updates at market close)

By Fergal Smith

Dec 17 (Reuters) - Canada's main stock index ended lower

for a fourth straight day on Tuesday as lower commodity prices

weighed on resource shares and political turmoil added to

headwinds for the Canadian economy.

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

ended down 27.50 points, or 0.1%, at 25,119.71, its

lowest closing level since Nov. 20.

U.S. stocks posted bigger declines as investors exercised

caution ahead of a Federal Reserve policy announcement on

Wednesday.

"The Canadian economy is still struggling and it's kind of

rudderless at the moment with the threat of tariffs, the turmoil

in the government, the currency under siege," said Colin

Cieszynski, chief market strategist at SIA Wealth Management.

Canadian Prime Minister Justin Trudeau is reflecting on

complaints about his leadership by legislators from the ruling

Liberal Party who are unhappy that Finance Minister Chrystia

Freeland quit, a close ally said.

The Canadian dollar weakened to nearly a five-year low

against its U.S. counterpart.

Domestic inflation data for November was mixed. It showed

the annual rate dipping unexpectedly to 1.9% but measures of

underlying price pressures watched closely by the Bank of Canada

were higher than expected.

The energy sector fell 0.7% as the price of oil

settled 0.9% lower at $70.08 a barrel on demand worries

following the release of negative economic news from Germany and

China.

Gold and copper prices also fell, while the

materials sector, which includes metal miners, lost 0.3%.

Heavily weighted financials also ended 0.3% lower.

Shares of Air Canada tumbled 9.4% as the company forecast

its 2025 adjusted earnings before interest, taxes, depreciation,

and amortization in the range of C$3.4 billion ($2.38 billion)

to C$3.8 billion, compared with analysts' estimates of C$3.63

billion.

Technology was a bright spot, rising 0.9%, helped by a gain

of 3.4% for e-commerce company Shopify Inc. ( SHOP )