; briefing requirement (a) Office of the Chairman of the Joint Chiefs of Staff Of the amounts authorized to be appropriated by this Act for fiscal year 2024 for operation and maintenance, Defense-wide, and available for the Office of the Chairman of the Joint Chiefs of Staff for travel expenses, not more than 80 percent may be obligated or expended until the date that is 15 days after the date on which the Secretary of Defense submits to the Committees on Armed Services of the Senate and House of Representatives the risk assessment mandated by paragraph (2) of subsection (b) of section 153 of title 10, United States Code, and required to be submitted pursuant to paragraph (3) of such subsection by not later than February 15, 2024. (b) Office of the Secretary of Defense Of the amounts authorized to be appropriated by this Act for fiscal year 2024 for operation and maintenance, Defense-wide, and available for the Office of the Secretary of Defense for travel expenses, not more than 80 percent may be obligated or expended until the date that is 15 days after the date on which the Secretary submits to the Committees on Armed Services of the Senate and the House of Representatives the risk mitigation plan required to be submitted as part of the assessment referred to in subsection (a), if applicable. (c) Briefing requirement Section 153 of title 10, United States Code, is amended by adding at the end the following new subsection: (d) Briefing requirement (1) Not later than 15 days after the submission of the risk assessment required under subsection (b)(2) or March 1 of each even-numbered year, whichever is earlier, the Chairman shall provide to the Committees on Armed Services of the Senate and the House of Representatives a briefing on the activities of the Chairman under this section. (2) The briefing required under paragraph (1) shall include— (A) a detailed review of the risk assessment required under paragraph (2) of subsection (b), including how such risk assessment addresses the elements required in