Image copyright AP Image caption New transport minister Lisa Raitt (right) is among the current cabinet members to change posts

Canadian Prime Minister Stephen Harper has unveiled a major cabinet reshuffle in the wake of a Senate expenses scandal that hit his party's image.

Among the eight new ministers announced on Monday were four women.

Finance Minister Jim Flaherty and Foreign Affairs Minister John Baird are among those to keep their posts.

Mr Harper first announced the changes on Twitter, where he said he was "proud to be naming four new strong, capable women to the Ministry".

The shuffle also comes as Mr Harper and the current Conservative government prepares for the 2015 election.

On Monday, the prime minister said the appointments would "carry our new agenda forward".

Housing expenses fiddle

Among the new cabinet members are Labour Minister Kellie Leitch and Heritage Minister Shelly Glover. Diane Finley becomes public works minister and Steven Blaney, formerly minister for Francophonie, becomes public safety minister, replacing a recently resigned Vic Towes.

Several existing cabinet members also changed posts. Defence Minister Peter MacKay and Justice Minister Rob Nicholson swapped jobs.

Leona Aglukkaq becomes environment minister, a move from health, while Lisa Raitt, the former labour minister, will now handle transport. Rona Ambrose takes over at the health ministry.

Four Canadian senators have faced scrutiny since December for their official expenses.

The Senate's internal economy committee has demanded hefty sums be repaid by Conservative Senator Mike Duffy, Liberal Senator Mac Harb and Conservative Senator Patrick Brazeau, who is on a leave of absence over a separate matter - a criminal complaint of assault and sexual assault.

Senator Pamela Wallin resigned in May from the Conservative caucus over an ongoing audit into her travel expenses.

Mr Harper has said he had no knowledge of his chief-of-staff's decision to give Sen Duffy C$90,000 ($86,000; £57,000) to repay improperly claimed housing expenses.

Court documents show the chief of staff told three other employees in the prime minister's office.

Canadian senators are appointed on the advice of the prime minister and may serve in the Senate until age 75.