The federal government will soon decide the fate of the army's fleet of aging Leopard tanks, some of which are being used by Canadian soldiers in Afghanistan.

"I know we'll have an announcement on that very shortly," Prime Minister Stephen Harper said in Kitchener, Ont. on Tuesday.

"I'm not sure what position we're in, I can just say that cabinet has been discussing the tank issue."

The head of the Canadian army, Lt.-Gen. Andrew Leslie, says the Leopard C2 tanks need to be retired soon.

Seventeen are in use in Afghanistan and, lacking air-conditioning, they cook in the searing Afghan summers, with temperatures inside the vehicles soaring to 60 C, the army says. At the same time, spare parts for the aging vehicles are becoming hard to find.

"The current tank force is over 30 years old," Leslie said while visiting soldiers in Kandahar. "They have provided sterling service over three decades, but they are definitely at the end of their legs."

"We, the army, the government of Canada, have a variety of choices that we will have to work through."

Leslie said the government has to decide whether to replace the vehicles, and if so, what to purchase in their place.

One option is to lease 20 state-of-the-art German tanks, known as Leopard A6Ms. Media reports on Tuesday suggest that option is being seriously considered by the government.

When asked about the option, Defence Minister Gordon O'Connor smiled to reporters, but refused to confirm the deal.

"Are we getting new tanks? I don't know anything about that," he said in Montreal.

Heat taking its toll, Leslie says

Leslie said whatever the decision, something needs to be done. The army worries about the toll the heat inside the vehicles will take on its soldiers.

"We will have to restrict their operations because we are not going to lose soldiers because they overheat," Leslie said. "We will restrict their operations to more cooling periods of the day."

The army has been considering ways to keep the tanks cooler, but Leslie said the ultimate solution is more modern vehicles.

In 2003, the previous Liberal government announced it would scrap the tanks and spend $600 million to replace them with the Mobile Gun System, an eight-wheeled light armoured vehicle with a cannon mounted on top.

The tanks were originally developed in Germany in the 1960s. Canada bought 127 Leopard tanks in 1978-79 and upgraded them. According to the Department of National Defence, the tanks can remain in service until 2010.

'Tanks are very important': O'Connor

O'Connor acknowledged on Tuesday how important the tanks are, especially when it comes to protecting troops.

"When I was in the army many years ago, we never thought of putting armour all around the cab of the truck. We now have 85 trucks on order with armoured cabs.

"We are armouring everything and we are trying to protect the lives of our soldiers."

O'Connor said the army is continuing to increase the use of armoured vehicles in Afghanistan: "You'll notice in the last six months that the number of casualties has gone down. Tanks are very important."

Canada has more than 2,000 troops in Afghanistan, with the majority stationed in the southern province of Kandahar.

Forty-five Canadian soldiers have been killed in Afghanistan since Canada sent troops to the troubled country in early 2002.

With files from the Canadian Press