OTTAWA -- Tampons will be a little cheaper as of Canada Day now that the Conservative government is moving to exempt feminine hygiene products from GST.

The House of Commons unanimously adopted an NDP-sponsored motion calling for the change earlier this month -- a motion that passed after women in the Conservative caucus threatened to boycott the vote if their party didn't approve.

Opponents of the tax have long decried it as being entirely discriminatory, as it is only paid by women, and on an essential product, while other goods deemed as luxuries escape the levy altogether.

After the motion passed, the government said they would make the change in a future budget bill, but on Thursday a notice appeared from Finance Canada that the tax would indeed disappear on July 1.

Why the change is happening now wasn't immediately clear. Finance Minister Joe Oliver, who is overseas for G7 meetings, was not available for comment. Conservative MP Michelle Rempel called the change in line with the government's lower-tax policies.

The New Democrats suggested another reason -- it's an election year.

"Women have made it very clear that they are paying attention," said MP Irene Mathyssen, who brought the motion before the Commons and also had a private member's bill on the subject.

"After 25 years you run out of excuses of why there's a discriminatory tax on the books."

Why feminine hygiene products weren't exempted from the GST when it was implemented, when other essential goods were, is unknown though several provinces do not add their sales taxes to the goods.

Legislative efforts to remove the GST date back years, but the idea found added support this year with an online petition that eventually received more than 70,000 signatures.

Jill Piebiak, a political activist and the petition's founder, said she was thrilled when the motion was passed, but didn't know what to expect next, given the government's vague future commitment.

She said she's overjoyed to hear the tax is coming off as of July, citing strong female leadership on both government and opposition benches. But she also called it a testament to the power of the grassroots.

"I think people should continue to speak up when they see injustice and work hard to change it," she said. "This campaign shows that it can be done."

The Finance Department notice says the tax will no longer apply to "a supply of a product that is marketed exclusively for feminine hygiene purposes and is a sanitary napkin, tampon, sanitary belt, menstrual cup or other similar product."