The media will be barred from the airfield at Canadian Forces Base Trenton, Ont., when a plane carrying the remains of four Canadian soldiers killed in Afghanistan lands Tuesday evening.

In the past, television and print media have been invited to attend when bodies of Canadian soldiers who have fallen overseas are repatriated.

But on Monday evening, news organizations were informed of the unprecedented media ban at CFB Trenton.

Government officials said the policy is permanent.

The move echoes an attempt in 2003 by the administration of U.S. President George W. Bush. Worried over diminishing public support for the Iraq war, Washington imposed a publication ban on images of coffins carrying the bodies of American soldiers.

Now, with polls showing Canadians almost evenly divided on the mission in Afghanistan, the federal government may have similar concerns.

CTV's chief political correspondent said the Conservative government may be worried that Canadians fear Afghanistan could become Prime Minister Stephen Harper's Iraq.

"(The government) is afraid that Canadians, seeing the bodies, seeing the coffins, that the images are so strong it's turning people off on the mission," said Craig Oliver.

But Defence Minister Gordon O'Connor said politics had nothing to do with the decision.

"I have made the most appropriate decision during this most emotional time for the families," O'Connor told The Canadian Press.

"The repatriation of our fallen soldiers back to Canada is a private and solemn event between the families and the Canadian Forces."

Some Opposition members say Canadians shouldn't be kept blind to the human cost of conflict.

"They're modeling their approach a little bit on the way George Bush and the American administration has approached it," NDP Leader Jack Layton told CTV. "I don't think it is the right way to go."

But Tory MP Brian Pallister said the government is adjusting to the changing situation in Afghanistan.

Pallister told CP that this country's soldiers are "closer to the action" than at any time in recent years, and the impact of casualties returning home must be taken into account.

Harper is not expected to travel to CFB Trenton to meet the coffins when they land in Canada. The Globe and Mail reports that O'Connor and Gen. Rick Hillier, Chief of the Defence Staff, will likely be there.

In April 2002, then-prime minister Jean Chretien, the defence minister and chief of the defence staff attended a ceremony at Trenton after four soldiers were killed in Afghanistan that month.

Flag decision

News of the media ban comes on the same day O'Connor defended a new policy not to lower flags on government buildings to half-mast every time a Canadian soldier is killed.

In a Monday letter to The Globe and Mail newspaper, O'Connor said the newly elected Conservative government is returning to a policy where the flag on the Peace Tower is only lowered on one day a year -- Remembrance Day.

"The previous Liberal government broke with this long-standing tradition that confidently brought Canada through its wartime history and instead decided on an ad-hoc basis to lowering the flag of the Peace Tower," he wrote.

"As Minister of National Defence, I can tell you that this adhockery unfairly distinguished some of those who died in Afghanistan from those who have died in current and previous operations.

"Lowering the Peace Tower's flag on November 11th ensures that all of Canada's fallen heroes are justly honoured."

In the event that a soldier dies in combat, flags will be put at half-mast within the operational base, the home base of the member and the National Defence Headquarters from the day of death until sunset on the day of the funeral.

Also, all flags within the service (Navy, Army, or Air Force) of the member will be half-masted from sunrise to sunset on the day of the funeral, the letter says.

The change in flag protocol comes as the bodies of four Canadian soldiers begin their journey home.

Cpl. Randy Payne, Cpl. Matthew Dinning, Bombardier Myles Mansell and Lieut. William Turner were killed in a roadside bomb attack in Afghanistan over the weekend.

The latest attack on Canadian soldiers in Afghanistan will lead to further debate on extending the mission, Liberal Defence Critic Ujjal Dosanjh told CTV's Question Period on Sunday.

"Canadian public opinion is already divided," Dosanjh said. "There's no question in my mind that as more casualties continue to happen, Canadians will increasingly ask more questions.

"It's appropriate for Canadians to ask questions -- they always have. They support our troops. We support our troops. Despite that, there might be questions and we as politicians need to be ready to answer them."

Meanwhile, Alberta Premier Ralph Klein says flags at the legislature will be lowered to half-mast.

Klein said Tuesday that this is what most Albertans would want, as an act of respect for fallen soldiers. He said when soldiers, either from his province or stationed in his province die, flags will be lowered the day of the funeral.

Canadian flags outside post offices in Edmonton are also at half-mast -- Lieut. Turner was a part-time army reservist who worked in that city as a letter carrier.

"It is important because (Turner) was one of our members,'' Ramon Antipas, president of the Canadian Union of Postal Workers local, told The Canadian Press. "He truly believed in the mission. This is in recognition for what he was doing."

The mayor of Toronto has also made a decision to lower the flag atop Toronto City Hall, beginning Tuesday, to half-mast in honour of the four Canadian soldiers.

One of the soldiers, Cpl. Dinning, was from the Toronto area.

Flags have been lowered at the soldiers' home bases and at National Defence Headquarters in Ottawa.

A total of 15 Canadian soldiers and one diplomat have died since 2002, when Canada first became involved in Afghanistan following the ouster of the hard-line Taliban regime.

With files from CTV's chief political correspondent Craig Oliver and The Canadian Press