HALIFAX - Nova Scotia's six Liberal MPs plan to speak out Monday against Ottawa's plan to fix the fiscal imbalance introduced in last week's federal budget.

Nova Scotia and Newfoundland and Labrador signed deals with the former Liberal government in 2005 that would have ended the practice of clawing back equalization money based on offshore revenues.

But last week, the federal Conservatives gave both provinces the option to choose between a new formula that includes 50 per cent of resource revenues in equalization calculations, or maintain the status quo.

Nova Scotia's Tory government begrudgingly opted into the new formula, which will provide more money immediately but puts the province at risk of losing money from oil and gas resources in the future.

Liberal MP Scott Brison, who represents the riding of Kings-Hants, says he was shocked that the provinces were asked to effectively abandon the offshore accords they fought adamantly for two years ago.

Brison says Prime Minister Stephen Harper has turned his back on both provinces.

"This (federal) budget has built a welfare wall around Atlantic Canada, and has made it far more difficult for us to become a 'have' region," he says.

"Ripping up those accords would never be an option in a Liberal government."

While Ottawa argues the provinces were given a choice, Nova Scotia Premier Rodney MacDonald has said his province, which has long fought for a better equalization deal, had little option but to take more money now and effectively ditch the offshore accord.