Canada signed the Convention on Cluster Munitions in 2008, but the Conservative government waited until last year to introduce the legislation that would ratify it.
The legislation has sparked criticism because it contains a provision that would allow the Canadian Forces to be involved in the use of cluster bombs in joint operations with the United States, which has opted out of the convention.
Opposition parties say the bill does not conform to the letter or the spirit of the convention — banning the use of cluster munitions.
The bill passed second reading on Wednesday and was referred to the House of Commons foreign affairs committee.
The government introduced the bill in the Senate last fall, where the so-called "loophole" on interoperability was criticized by various civil society groups and opposition Liberal senators.
The Conservative majority in the Senate passed the bill without amendments.
On Tuesday in the Commons, the Conservatives used a parliamentary procedure to limit debate on the bill to five hours.
The Tories say they want to pass the bill quickly, but the move sparked outrage on the opposition benches.
NDP foreign affairs critic Paul Dewar told the debate, which lasted until 11 p.m., that the government's intent was to "ram" the bill through the Commons.
He criticized the government for introducing the bill in the House in the wee hours of a marathon sitting two weeks ago.
"The Conservatives had one speaker on it at midnight; that is how seriously they take it. They then brought in closure on it," said Dewar.
"After having heard what happened in the Senate, they feel that the bill is OK the way it is, because I suspect that they are going to ram it through."
A single cluster bomb contains hundreds of baseball-sized explosives that often fail to detonate and can lie dormant for decades, posing an ongoing hazard to innocent civilians, especially young children in dozens of post-war countries.
"We need to take it more seriously, and we need to see amendments," said Dewar.
Defence Minister Peter MacKay defended the bill because he said it preserves the need for Canadian troops to work with those of their top ally, the U.S.
"This is an honourable compromise. This is the way to move the legislation forward, to move forward with a ratification of the convention, and allow us to continue to act interoperably with our allies," said MacKay.
He said Canada's allies, the United Kingdom and Australia, have similar provisions on interoperability in their enabling legislation.
Paul Hannon, the executive director of Mines Action Canada, said Canada's proposed legislation is weaker than that of its allies, and should be subject to a closer examination by the Commons foreign affairs committee.
"We think things are progressing far too quickly and in a chaotic way," said Hannon.
"Canada needs to show leadership by making sure we have the best possible legislation."
Sarah Blakemore, the head of the Cluster Munition Coalition, an international collection of civil society groups, called on the government to amend the bill.
"As written, this bill does not reflect Canada's leadership on humanitarian disarmament issues. The Convention on Cluster Munitions is about prevention of future tragedies and the protection of civilians, and the loopholes found in Bill S-10 run counter to this intent," Blakemore said in a statement.
Canada's lead negotiator of the convention resigned in protest from the Foreign Affairs Department two years ago because of concerns he had about the interoperability clause in the bill.
Earl Turcotte told a Senate committee last fall that Canada would be setting "a dangerous precedent" that would undermine international law and weaken the convention by passing the bill as is.
"This would be a betrayal of the trust of colleagues in other countries who negotiated the convention in good faith, a betrayal of Canadians who expect far better from our nation and, worst of all, a complete failure to do everything we can to prevent more needless deaths and suffering among innocent men, women and children," he told the senators last October.
Liberal foreign affairs critic Bob Rae said Turcotte should be called to testify before the Commons committee.
"Canada should not be escaping its responsibilities by choosing to implement a treaty in this way," said Rae.
"It makes a mockery of our understanding of what it means to actually put into effect and to put into operation a treaty obligation that we signed."