The Prime Minister has refused to comment on news media reports that a Canadian naval officer may have compromised intelligence gathered by New Zealand.
Jeffrey Paul Delisle was arrested in January and is accused of selling intelligence gathered by the United States, Britain, Canada, Australia and New Zealand to Russian agents.
Sub-Lieutenant Delisle is due to appear before the Nova Scotia supreme court for a preliminary hearing in October.
But John Key would not confirm whether Canadian authorities have contacted the Government about the matter.
Nor would he say whether he would raise the matter with the Russian President Vladimir Putin, when he next meets him.
Documents issued under Australian freedom of information laws involve the Australian High Commissioner to Canada discussing the case with Canadian Prime Minister Stephen Harper soon after the arrest.
The Fairfax Media says it has been told by Australian security sources that Sub-Lieutenant Delisle's access was "apparently very wide".