OTTAWA -- The federal government's tough-on-crime agenda is "excessively punitive" for youth and is a step backwards for Canada's child rights record, says a United Nations group.

The UN committee on the rights of the child has finished a 10-year review of how Canada treats its children and how well governments are implementing the Convention on the Rights of the Child.

In particular, the committee says Canada's Youth Criminal Justice Act complied with international standards until changes were introduced earlier this year.

The Harper government's Bill C-10 -- an omnibus crime bill that includes stiffer penalties for youth and makes it easier to try them as adults -- no longer conforms to the child rights convention or other international standards.

Bill C-10 "is excessively punitive for children and not sufficiently restorative in nature," the committee wrote in a report published over the weekend.

"The committee also regrets there was no child rights assessment or mechanism to ensure that Bill C-10 complied with the provisions of the convention."

The committee also repeatedly expressed its concern that aboriginal and black children are dramatically overrepresented in the criminal justice system. Aboriginal youth are more likely to be jailed than graduate from high school, the report said.

In order to meet the standards of the UN convention, Ottawa should raise the minimum age of criminal responsibility and ensure that no one under 18 is ever tried as an adult, the report said.

Authorities should also be developing alternatives to detention, writing rules to restrain the use of force against children in detention and to separate girls from boys in jail, the committee added.

Governments should determine why so many aboriginal and black children and youth are involved in the criminal justice system and figure out how to reduce the disparity, the report recommended.

The committee also chastised Canada for failing to provide equal social services to aboriginal children -- especially in the realm of child welfare, an issue now before Canadian courts.

It accused authorities of "serious and widespread discrimination" in the services they offer aboriginal children, visible minorities, immigrants and children with disabilities.

"The UN joins the auditor general, leading experts and First Nations in calling on the federal government to step up to the plate and ensure equity for First Nations children," said advocate Cindy Blackstock of the First Nations Child and Family Caring Society.

"There is simply no excuse for a government to discriminate against children."

The child rights convention is a binding international treaty that Canada ratified in 1991. Signatories are obliged to defend their child rights' records and explain progress at regular intervals before a UN committee.

Canadian officials appeared before the committee two weeks ago.

They did not respond to requests for comment about the final report on Tuesday, partly because it was unclear who in government is responsible.

But previously in the House of Commons, Conservative parliamentary secretary Bob Dechert lashed out at the UN committee because one of its members is from Syria.

"Syria, a country whose rulers are stealing the innocence of an entire generation of its children, is criticizing Canada," he said. "Imagine that.

"This is no doubt to distract from the atrocities that Syrian children are currently facing every day."

But critics say Ottawa is wrong to write off the UN committee -- even if Canada is not among the worst offenders.

"You can't sign on to a treaty like the Convention on the Rights of the Child without adhering to the guidelines that it lays out," said Jaskiran Dhillon, a representative for Justice for Girls.

"It sets an international bar for what treating and taking care of your children and youth looks like. It doesn't mean that you disregard the most marginalized ... populations of your country."