WASHINGTON, February 12--Secretary of War Patterson declared tonight that if the proposed cut in the Army budget is made, "The current and long-term missions of the Army, including those of General MacArthur in Japan and General McNarney in Germany, will be jeopardized."

Earlier, the Navy had contended that even a $500,000,000 cut in its funds might make the fighting fleets "immobile and impotent as an instrument of national policy."

The Army-Navy stands were occasioned by announced plans of a House-Senate budgetary subcommittee to slash President Truman's $37,500,000,000 Federal budget figure by a total of $6,000,000,000.

Patterson said that the War Department budget as submitted by President Truman to Congress "was down to the minimum our leaders believed necessary for support of our occupation forces overseas and for reasonable guarantees for national security."