Ministry of Defence (Brunei)

The Ministry of Defence Brunei Darussalam (Kementerian Pertahanan), officially abbreviated as MinDef, is a cabinet-level ministry of the Government of Brunei. It is responsible for the national security and its military forces within the sultanate of Brunei Darussalam; the latter collectively known as the Royal Brunei Armed Forces (RBAF); Angkatan Bersenjata Diraja Brunei, (ABDB). MinDef is Brunei's ministry of defence; and was established on January 1, 1984, when Brunei Darussalam achieved independence from the United Kingdom. The Ministry of Defence leadership presently consists of a minister (First Minister); its incumbent is the Sultan of Brunei, Hassanal Bolkiah,  who is also the Supreme Commander of the RBAF / ABDB. A deputy minister (Second Minister, officially styled Minister of Defence II) is second-in-command at the Ministry of Defence.

The Ministry of Defence is headquartered within Bolkiah Garrison in Bandar Seri Begawan, the capital of Brunei Darussalam, in the Brunei-Muara District, with the postcode BB3510. In late 1986, the Ministry of Defence was restructured and reorganised; it currently manages the Royal Brunei Armed Forces, the Royal Brunei Malay Reserve Unit, and also the Gurkha Reserve Unit. The ministry is sub-divided into two divisions; Civilian Staff (headed by a Permanent Secretary), and Military Staff (headed by Commander of Royal Brunei Armed Forces).

Leadership
The First Minister of Defence (Menteri Pertahanan) upon the inception of the ministry was Sultan Omar Ali Saifuddien III, who was the late father of the current Sultan, Hassanal Bolkiah, and had been the preceding Sultan of Brunei until his abdication in 1967. Upon the death of Sultan Omar Ali Saifuddien III in 1986, Sultan Hassanal Bolkiah assumed the position, and has remained the First Minister to the present day.

The Second Minister of Defence (Menteri Pertahanan Kedua) portfolio was established in 2018 as a result of a cabinet reshuffle, and was held by Halbi Mohd Yussof.

The Deputy Minister of Defence (Timbalan Menteri Pertahanan) portfolio first appeared in the cabinet assembly in 1986. The position of Deputy Minister of Defence was abolished when the cabinet reshuffle in 2018 established the portfolio of Second Minister of Defence. However, in 2022, there was no longer a Second Minister at the defence ministry, and the portfolio of Deputy Minister of Defence reappeared as a result of cabinet reshuffle. The incumbent was Abdul Razak Abdul Kadir, who took office from 7 June 2022 until his termination, alongside the abolishment of its office on 27 February 2023. Following the termination, Halbi Mohd Yussof was appointed temporarily as the current Second Minister of Defence, in addition to his present appointment as Minister at the Prime Minister's Office.

Budget
The allocated budget for the fiscal year 2022–23 was 597.67 million Brunei dollar (B$ or BND), an increase of two percent from the previous year. The fiscal year 2024–25 seen a 28% increase in defence spending over the 2023–24 figures, with a record spending of B$796.3 million being announced.