A Nova Scotia Conservative MP has followed through on his threat to vote against his government's budget to express his displeasure with how it treats the Atlantic Accord on offshore resources.

And as a result, Bill Casey has been ejected from the Conservative caucus.

"He knew the consequences of his action," said Government Whip Jay Hill.

There were big cheers from the opposition and glum faces on the Tory colleagues of Casey after Tuesday evening's vote, even though the preliminary motion passed 158-108.

A more important vote on Bill C-52's third reading will take place later this week.

Casey said he'd been working on the issue for weeks and had raised it with Prime Minister Stephen Harper and Finance Minister Jim Flaherty before the vote.

Casey said earlier Tuesday he would find it simple but not easy to vote his conscience.

"It's not easy, but it is simple in a way: If the government of Canada will not honour a contract, then it's easy for me to do it," he said on CTV's Mike Duffy Live.

But he added he knew there was a risk he would be kicked out of caucus.

"If the government of Canada can't honour a contract, then we'll have to live with the consequences," he said.

Casey is upset that the 2007 budget effectively kills the 2005 accord, which deals with revenues from offshore resources.

In the House of Commons question period, Finance Minister Jim Flaherty indicated he wasn't prepared to budge. Casey met with him Monday night.

There was another meeting on Tuesday morning. Casey said he wasn't invited to that one.

Peter Van Loan, the government's house leader, noted on MDL that the Liberals expelled Joe Comuzzi after the veteran Liberal voted for the 2007 budget.

"Obviously budget bills are the most important bills for any government," he said.

Van Loan added that the Atlantic Accord is protected by the budget, but only if they opted to stay with the older equalization formula.

But Liberal House Leader Ralph Goodale said the agreement specifically states that if the equalization arrangements change in the future, Nova Scotia and Newfoundland won't be barred from benefiting from those improvements.

"That is clearly what is in the deal. The government of Canada is breaking the deal," he said.

NDP House Leader Libby Davies said Casey must believe the agreement was broken, "otherwise, why would he be voting against something as serious as a budget?"

Nova Scotia Premier Rodney MacDonald, a Conservative, wouldn't comment. But Saskatchewan Premier Lorne Calvert, who has himself been feuding with his federal counterparts over equalization, praised Casey.

"The question many people in Saskatchewan are asking, including myself is: where are our members of Parliament?" Calvert told The Canadian Press. "'Where is the courage to stand up for their province?"

With files from The Canadian Press