The federal government is rejecting renewed calls for a public inquiry into missing and murdered aboriginal women in advance of a meeting Wednesday between premiers and native leaders, one of whom says the prime minister is isolated in his position.

The premiers and aboriginal leaders endorsed the idea of an inquiry when they met last year, but there is growing momentum behind such a proposal, said Ghislain Picard, national chief of the Assembly of First Nations.

"The difference between last year and this year is that there is more and more support," Picard said in an interview ahead of the meeting in Charlottetown.

"What we have today is that the federal government is standing alone."

Native leaders say the need for an inquiry has been highlighted by the death earlier this month of a 15-year-old aboriginal girl whose body was found wrapped in a bag that was dumped in the Red River in Winnipeg.

Tina Fontaine had been in the city for less than a month when she ran away from foster care. Police are treating the case as a homicide.

"In light of recent events ... it's clear that this issue cannot be overshadowed by other pressing issues," Picard said.

Prime Minister Stephen Harper said last week that cases like Fontaine's should not be viewed as a "sociological phenomenon" but rather a serious crime to be investigated by police.

The federal government says it is taking steps to deal with the problem of violence against aboriginal women, such as setting up a national DNA missing person's index and introducing tougher sentences for murder, sexual assault and kidnapping.

"We don't need yet another study on top of the some 40 studies that have already been done," a spokeswoman for Justice Minister Peter MacKay said in a statement.

"We need police to catch her killer and ensure the perpetrator or perpetrators are punished and face the full force of the law."

The Canadian Association of Chiefs of Police also decided Tuesday against endorsing an inquiry, saying it was up to all levels of government to take immediate action to address the underlying issues that lead aboriginal women to be vulnerable to crime and violence.

Newly elected association president Clive Weighill, chief of the Saskatoon police, said the group's board of directors met to discuss the issue and they fear an inquiry will only delay action.

But several premiers including Ontario's Kathleen Wynne, Manitoba's Greg Selinger and Brad Wall of Saskatchewan have spoken out in recent days calling on the federal government to change its mind.

Wynne said Harper's comments were "outrageous," suggesting the prime minister is ignoring the systemic problems behind the violence faced by aboriginal women.

Wall said the provinces remain united with aboriginal leaders.

"Saskatchewan, on a percentage basis, has a high First Nations and Metis population ... so we'd like to see it the subject of an inquiry," he said in an interview.

"There's a societal element that we do need to look at and the provinces and the federal government bear responsibility in that regard."

Michele Audette, president of the Native Women's Association of Canada, said an inquiry could take years to complete its work, which is why she would like to see a federal-provincial working group established to spur some action.

Audette said her roundtable proposal would bring together federal and provincial ministers responsible for various programs affecting aboriginal people.

"It would help to stop working in silos," she said in an interview.

"And it would help end the broken relationship between indigenous people and this current government. ... If the federal government says no to this, it's obvious there's a huge problem here."

P.E.I. Premier Robert Ghiz said the call for an inquiry is part of the meeting agenda, but he is also interested in the roundtable idea.

"Dialogue is good," said Ghiz, who will be the longest-serving premier at the meeting. "If one door closes, you always have to look for another to open up."

The premiers will continue with their own meetings on Thursday and Friday. Ghiz said other items on the agenda include health-care innovation, internal trade, competitiveness and the temporary foreign worker program.

The long-term bid to create a national energy strategy will also be discussed, but Ghiz suggested he doesn't expect much progress because two of the largest energy-producing provinces -- Alberta and Newfoundland and Labrador -- are in the midst of replacing their premiers.