OTTAWA - Angry Canadian politicians say this country hasn't sacrificed soldiers' lives and spent billions of dollars in Afghanistan so that men there could be permitted to rape their wives.

Outrage mounted Wednesday over legislation that would restrict the rights of Afghanistan's minority Shia women and make it illegal for them to deny their husbands sex, leave the house without permission, or have child custody.

The Canadian government is spending $5 million on a separate project to reform Afghan family law and has been sideswiped by the controversial new legislation.

Prime Minister Stephen Harper said he's deeply troubled by a move which flies in the face of what the international community wants to accomplish in Afghanistan.

"This is antithetical to our mission in Afghanistan," he told a Canadian media outlet in London, where he's attending the G20 summit.

"The concept that women are full human beings with human rights is very, very central to the reason the international community is engaged in this country. . .

"It's a significant change we want to see from the bad, old days of the Taliban."

Canada has lost 116 soldiers and spent up to $10 billion to support the government of President Hamid Karzai. Several members of Harper's cabinet voiced similar outrage, as did opposition politicians and one military family.

"My son gave his life up for all these causes and to have President Karzai's government bring in a law like that, that's insulting," said Jim Davis of Nova Scotia, whose son, Cpl. Paul Davis, was killed in Afghanistan in 2006.

However, he agreed Canada must continue working to modernize the country.

Defence Minister Peter MacKay said he will use this week's NATO summit to put "direct" pressure on his Afghan counterparts to abandon the legislation.

"That's unacceptable - period," he said Wednesday. "We're fighting for values that include equality and women's rights. This sort of legislation won't fly."

The proposed Shia family law has cast a shadow over an international conference in Europe on Afghanistan's future.

Critics say Karzai approved the law in advance of his country's elections in the hope of winning critical swing votes from conservative Shia men.

But the law remains shrouded in mystery: it has not been published, Karzai's office has refused to comment on it, and its alleged details have only been made public by the Afghan parliamentarians who opposed it.

Confusion over the legislation is so widespread that even Afghan diplomats were caught off-guard by the news. Afghanistan's ambassador to Canada, Omar Samad, said he's unclear on its basic details and is seeking information from Kabul.

A Canadian NGO says it is already working on a $5 million, government-funded project to reform Afghan family laws.

The process involves Afghanistan's ministry of women's affairs, female politicians, Afghan scholars, and human-rights organizations. Public consultations are set to start this spring.

But one of the workers involved says the process has been undermined by Karzai's hastily conceived, highly secretive Shia Personal Status Law.

"This is a clear step in the wrong direction for the rights of Afghan women," said Alexandra Gilbert, project co-ordinator for the group Rights & Democracy, from Kabul.

"It was not open, it was undemocratic, there was no media present."

Afghanistan's 2004 constitution allows the Shia to establish their own family law - but its Article 22 also guarantees equal rights for women.

Gilbert said the new law was first brought to her group's attention by the female Afghan politicians fighting it.

In the end, she said, those critics managed to gain some concessions - like a clause that sets 16 as the minimum age for girls to be married.

But the debate unfolded quickly and the bill was approved by parliament without any public discussion, she said. A written copy of the legislation has still not been distributed publicly.

"It all happened very fast," Gilbert said.

U.S. Secretary of State Hillary Clinton reportedly upbraided Karzai over the law during this week's 80-country Afghanistan summit in The Hague.

Liberal Leader Michael Ignatieff said Afghan women who proudly emerged from polling stations with ink-stained fingers after having voted for the first time never voted for this.

He said Canada must express its outrage - not on behalf of Westerners, but on behalf of Afghan women.

That being said, Ignatieff argued that the current controversy doesn't make the Afghan mission less just.

"I don't think it calls into question what our troops are doing," Ignatieff said.

"What our troops are doing is providing basic security for the very women whose rights are being outraged here. That's what Canadian soldiers are doing - every day.

"They're out on the line, making sure that a woman can go out of her house, go shopping, and come home - and not get blown up. And I'm fiercely proud of that."