Prime Minister Stephen Harper will remind Canadians of his party's successes over the past year in government, and set his policy direction through to the next election in a major speech Tuesday that will set the course through to the next election.

Sources say his remarks are being talked about as a "mini-throne speech," with the broad strokes of what he plans to do on such major public policy issues as the environment and Senate reform.

The possibility of Harper making a major policy speech to articulate his next key priorities has been floating around since last fall.

Harper's government took power exactly a year ago with a set of five key priorities, including a cut to the GST and the passage of the Federal Accountability Act — accomplishments he intends to highlight to the Canadian Club luncheon.

But the next set of priorities have not been specifically outlined by Harper in any concrete way since that first speech from the throne last year.

Tuesday's speech will include key messages on Harper's goals for the environment — the burning issue on both Parliament Hill and in public opinion polls — sources say.

He's also expected to speak about his hopes for electoral and Senate reform, a package he started to put into play late last spring and last fall, with a plan for term limits and elections.

The speech helps form the backbone of an election platform, with a campaign potentially in the offing as early as this spring.

The broad policy outlines and Finance Minister Jim Flaherty's March budget will be a one-two punch of Conservative ideas, and a challenge to the opposition parties to come to the table with their own nascent platforms.

Several members of Harper's cabinet are expected to attend Tuesday's midday speech.