; (4) submit to the National Nuclear Security Administration a formal request, through the Nuclear Weapons Council, requesting that the Administration participate in and support the W80–4 ALT warhead project described in paragraph (3); and (5) designate the Department of the Navy as the military department to lead the W80–4 ALT nuclear weapon project for the Department of Defense. (b) Initial operational capability The Secretary of Defense and the Administrator for Nuclear Security shall take such actions as are necessary to ensure the program and project described subsection (a) achieve initial operational capability, as defined jointly by the Secretary of the Navy and the Commander of the United States Strategic Command, by not later than September 30, 2034. (c) Limitation on authority to approve production The Under Secretary of Defense for Acquisition and Sustainment may not approve a Full Rate Production Decision or authorize Full Scale Production (as those terms are defined in the memorandum of the Nuclear Weapons Council titled Procedural Guidelines for the Phase 6.X Process and dated April 19, 2000) for the W80–4 ALT project until authorized by Congress. (d) Briefing (1) In general Not later than January 15, 2024, and not later than each March 1 and September 1 thereafter, the Under Secretary of Defense for Acquisition and Sustainment, the Secretary of the Navy, the Administrator for Nuclear Security, and the Commander of the United States Strategic Command shall jointly provide to the congressional defense committees a briefing on the progress of the program and project described in subsection (a). (2) Contents Each briefing required under paragraph (1) shall include— (A) a description of significant achievements of the program and project completed during the period specified in paragraph (3) and any planned objectives that were not achieved during such period; (B) for the 180-day period following the briefing— (i) planned objectives for the program and project