OTTAWA -- A leaked letter shows the prime minister told Defence Minister Peter MacKay last spring that his initial budget proposals did not cut deep enough on the administrative side of National Defence.

The three-page letter -- dated June 15, 2012, and obtained by The Canadian Press -- was written to provide "guidance" to MacKay and General Walt Natynczyk as the Conservatives embarked on a rewrite of their marquee defence policy.

The document sheds light on the divide between Stephen Harper's office, determined to wrestle the deficit to the ground, and a defence establishment resolved to protect the budget gains of the last five years.

Harper's missive set out what cuts he was prepared to accept, what wouldn't work, and even suggests National Defence unload some of its surplus property.

A spokesman for MacKay says the government doesn't comment on leaked documents and remains focused on getting the military the resources and equipment it needs.