Kuwait's new crown prince, Sheikh Meshal al-Ahmad al-Jaber Al-Sabah, took his oath of office before parliament on Thursday, after being nominated by his half-brother, the new emir.
Sheikh Meshal, 80, a long-serving top security official, was unanimously approved by the National Assembly.
He swore to "defend the liberties, interests and properties of the people" and to safeguard the country's independence and integrity.
Kuwait's new emir, Sheikh Nawaf al-Ahmad Al-Sabah, was appointed on September 30 after his own half-brother, Sheikh Sabah al-Ahmad Al-Sabah, died at the age of 91 while being treated in hospital in the US.
Sheikh Meshal, 80, has been deputy chief of the Kuwait National Guard since 2004, largely staying out of the political scene and away from disputes within the royal family.
His appointment, rather than the selection of a next-generation candidate, is seen as a conservative choice that provides much-needed continuity.
"It's also a conservative selection in terms of ruling family politics. It avoids choosing among public rivals," Kristin Diwan of the Arab Gulf States Institute in Washington said in a tweet.
"It avoids the transition to the next generation."
In recent years, the ruling family has been exposing its differences, with lurid accusations of corruption and political conspiracies flying between some of its members.
Unlike other oil-rich Gulf states, Kuwait has a lively political life with an elected parliament that enjoys wide legislative powers, and political disputes are often fought out in the open.
The succession comes at a time when the country is facing some key issues, including whether to establish ties with Israel and how to respond to a slump in oil prices amid the coronavirus pandemic.
© 2020 AFP