OTTAWA Danielle Smith swore in as the premier of Canada's main oil-producing province on Friday, promising financial support measures, tax cuts and a pledge to push back against federal climate policies she says would harm the region's fossil fuel industry.

Smith secured her first election victory as United Conservative Party leader last month, defeating the left-leaning New Democratic Party to return to power for another four-year term with 49 seats in Alberta's 87-seat legislature.

The victory signaled a further rightward shift in the traditionally conservative province and put the populist premier on a collision course with Liberal Prime Minister Justin Trudeau over climate goals.

"Today marks the start of an exciting future," Smith said at a swearing-in ceremony in Edmonton, after unveiling her new cabinet. "Over the next four years, we will improve on the affordability measures we already have in place such as fuel tax relief and electricity and natural gas rebates."

Smith also repeated her claim that Trudeau's climate policies will destroy tens of thousands of jobs in the oil and gas sector, which contributes more than 20% to Alberta's annual Gross Domestic Product.

Trudeau's government is aiming to cut climate-warming carbon emissions 40-45% by 2030, but will struggle to meet that target without significant reductions from Alberta, Canada's highest-polluting province.

"We will vigorously and firm firmly defend our province from disastrous federal policies that would devastate tens of thousands of hardworking families," Smith said.

(Reporting by Ismail Shakil in Ottawa; Editing by Marguerita Choy)