OTTAWA - Opposition parties are slamming a Tory backbencher's motion against sex-selective abortion as a cynical bid to re-open the abortion debate.

But Tory backbencher Mark Warawa argues it's about protecting girls from "the worst form of gender violence - gendercide."

The motion, tabled by the B.C. MP in September, reads: "That the House condemns discrimination against females occurring through sex-selective pregnancy termination."

NDP Leader Thomas Mulcair said Wednesday his caucus will vote against M-408 and wouldn't be "duped" by what he saw as Warawa's sleight-of-hand attempt to get abortion on the agenda.

"The context of this particular motion is that is was presented within minutes after the last one (M-312) was defeated."

M-312, a motion seeking to have Parliament look at when life begins, was defeated 203-91 in the House last fall and widely seen as an attempt to re-open the abortion debate.

Interim Liberal leader Bob Rae said he understood the majority of Canadians were uncomfortable with the idea of sex-selective abortions.

"I don't condone discrimination in any way, shape or form," he said, but "this is a continuing effort by members of the Conservative party to continue to make abortion an issue."

Warawa called their stance "shocking."

"The motion is a first giant step in the right direction," he said, calling it "a simple but very strong and powerful condemnation."

M-408 is scheduled for debate in the spring.