Martin told reporters he was not surprised that Bush had brought up the national missile defense system during their talks in Ottawa Tuesday -- despite expectations in Canada the issue was not on the agenda.

"Whatever we decide," said Martin, "it will be in Canada's interests. We are a sovereign nation and we will make our own decisions on our air space.

"But we are opposed to the weaponisation of space," Martin said, minutes after seeing Bush leave for Washington after an overnight visit to Ottawa, and a sidetrip to Canada's Atlantic coast.

That formulation has been Canada's consistent position on the issue, as Martin's minority government tries to figure out how to handle what is a political hot potato.

Many experts believe a Canadian decision not to take part in the system could scupper the North American Aerospace Defence Agreement (NORAD) with Washington, and make Canada blind to any threats entering its airspace.

Bush said on Tuesday he and Martin had "talked about the future of NORAD and how that organization can best meet emerging threats and safeguard our continent against attack from ballistic missiles."

That comment ignited a minor media storm and exposed Martin to attack from political opponents, especially the left-wing New Democratic Party.

An opinion poll by CBC last week suggested that 52 percent of Canadians were opposed to the missile shield.

Martin was also vague about what, if any, role Canada might play in next month's crucial election in Iraq, after reports last week said Canada could please Washington by helping to set up and monitor the polls.

All rights reserved. � 2005 Agence France-Presse. Sections of the information displayed on this page (dispatches, photographs, logos) are protected by intellectual property rights owned by Agence France-Presse. As a consequence, you may not copy, reproduce, modify, transmit, publish, display or in any way commercially exploit any of the content of this section without the prior written consent of Agence France-Presse.