OTTAWA - The Tory government is set to announce the lease of helicopters and unmanned surveillance planes for the Canadian military in Afghanistan.

Defence Minister Peter MacKay and Public Works Minister Christian Paradis will be in the Montreal area to outline the lease of up to eight Soviet-style Mi-8 helicopters to transport battlefield supplies in Kandahar.

An official in MacKay's office, speaking on background recently, said the lease would be an interim measure until the Defence Department completes the $375 million purchase of six American-made CH-47-D Chinook helicopters.

The Boeing-manufactured Chinooks, which will be able to transport both troops and equipment, are being acquired from the U.S. Army in a government-to-government purchase.

The deal has been in the works since last winter and defence industry sources said Wednesday it has been tied up at the Pentagon level as U.S. Army lawyers poured over supposed "liability" issues related to the agreement.

Securing helicopter transport was a principal condition of the Manley commission report last winter and a key caveat of Parliament's extension of the combat mission until 2011.

Former defence minister Gordon O'Connor first proposed the purchase of medium-to-heavy lift helicopters over years ago and the government quickly identified the Chinook as its preferred choice - signalling it intended to sign a $4.2 billion sole-source deal with Boeing.

But the contract for 16 CH-47F--the latest variant of the rugged helicopter--has been mired in the bureaucracy.

Commanders in Afghanistan first began pleading for helicopter support two years ago in order to get Canadian troops off the bomb-strewn, bloody roads of Kandahar.

Since 2002, 88 Canadian soldiers have died in Afghanistan.

The Manley commission report last winter gave the Conservative government until February 2009 to come up with the helicopters and a flight of unmanned surveillance planes.

The announcement Wednesday will also include details of a contract, possibly worth $100 million, to lease a flight of uninhabited aerial vehicles -- or UAVs -- from MacDonald Dettwiler and Associates Ltd. and Israeli Air Industries Ltd.

The companies were selected a few weeks ago in a decision that was quietly announced at an international air show in Britain.

The Conservatives have dithered about purchasing a replacement for its existing Sperwer tactical UAVs, which are rapidly becoming outdated and short of spare parts.

A proposal to buy U.S.-made Predator drones was shot down by the federal cabinet a year ago because it would have involved another sole-source contract.