The F-35 Lightning II jet fighter can proceed toward its tenth production series, according to a new Pentagon procurement report. The primary contractor for the program, Lockheed Martin Corp. is authorized to purchase parts for the next series of production, though that stage of the program has not itself been authorized.

The U.S. Department of Defense approved funding worth $920 million for Lockheed’s “advanced procurement” needs, meaning the materials, parts, and systems sourced from the vast network of manufacturers supplying the F-35 program.

The F-35 is a stealth-enabled, single-engine aircraft in development for more than a decade, but due to be introduced this year by the U.S. Marine Corps.  The fighter jets also will be deployed by U.S. Air Force (which already is using the jets in air exercises), the U.S. Navy, and the U.K. Royal Air Force, as well as defense ministries in several NATO and other Allied nations.

According to reports, the DoD and Lockheed continue to negotiate actual terms for the price of the jets in the tenth batch.

The F-35 program remains controversial because of the cost of the jets, which have vastly exceeded projections over many rounds of development, and now are reportedly ranging from $80 million to $100 million per jet.

Last year, Lockheed Martin and two of its largest partners in the F-55 program, Northrop Grumman and BAE Systems, agreed to meet new lower-cost targets set by the DoD. The agreement, which is called “The Blueprint for Affordability,” was developed to reduce the price of each F-35 to match its equivalent aircraft currently in service for the armed forces — notwithstanding the various technological advances to be included in the F-35.

Earlier this year, Lockheed Martin’s F-35 program manager reported that the cost-saving initiative had begun to show results, and that further savings might be expected when the tenth series of jets is officially authorized for production.

There are different versions of the F-35 for ground attack, reconnaissance, and air-defense missions.

The 78 jets to be built in the tenth series will be F-35 A’s for the USAF, and Australian, Italian, Norwegian, and Turkish air forces; 14 F-35 B’s for the USMC, U.K.’s Royal Air Force and the Italian Air Foce; and two F-35 C jets for the U.S. Navy and USMC.