If approved, the move would bump planned acquisition of 35 stealthy new fighters beyond the Navy's proposed new six-year spending plan, freeing up more than $1 billion between fiscal years 2008 and 2013 that officials hope to redirect to other naval priorities, these officials said.

The Navy and Marine Corps' fiscal year 2008 to 2013 program objective memorandum, submitted to the Office of the Secretary of Defense earlier this month, includes changes to the JSF program that reflect an agreement between the sea services to postpone initial operating capability by 14 months, said Pentagon officials.

This bid, which is subject to review -- and possible modification or even reversal -- by OSD, would delay fielding of the first Marine Corps JSF squadron from 2011 to 2012 and the Navy and Air Force variants would shift from 2013 to 2014, officials familiar with the spending proposal said.

Sources familiar with the POM proposal say the total planned buy of F-35 aircraft remains unchanged. However, if this schedule change is approved, the delay is likely to incur new costs, which could eventually eat into available funds for procurement, Pentagon officials said.

By pushing the planned acquisition of 35 aircraft beyond 2013, the sea services hope OSD will allow it to redirect the remaining resources to pay for other priorities, said one official, who asked to not be identified because the proposed spending plan is not a public document.

Navy officials in recent months have, for example, argued that shipbuilding accounts are not adequately funded.

This element of the Navy-Marine Corps POM follows a wide-ranging review of naval aviation capabilities -- with an eye to controlling program costs -- ordered at the beginning of the year by Chief of Naval Operations Adm. Michael Mullen.

Kathy Crawford, a spokeswoman for the Joint Strike Fighter program, declined to comment on the Navy-Marine Corps POM, which she said reflected a proposal that is subject to further deliberations.

The proposal, if approved, would be the second significant schedule change for the JSF in the last two years. In 2004, weight issues prompted the program to be delayed, a shift that drove costs up.

A delay in the production schedule could also have implications for the nine-nation international partnership working with the U.S. military to develop the new fighter.

The Defense Department in December hopes to secure commitments for JSF procurement from Britain, Italy, the Netherlands, Norway, Turkey, Spain, Canada, Australia and Denmark, each of which has invested in the new aircraft's development and influenced its requirements.