President Rodrigo Duterte sees economic zones as key to boosting investment in the Philippines and creating jobs, particularly in less developed areas outside the capital.
Plaza said defense companies from Korea, Israel, China and Russia have expressed interest in setting up shop in the Philippines.
Among areas under consideration are Camp Evangelista on Mindanao island and parts of Fort Bonifacio in Manila.
Plaza helped companies in industrial parks win government approval for tax deductions for the cost of Covid mitigation.