In this file photo taken on May 31, 2009, then Kuwait's Crown Prince Sheikh Nawaf al-Ahmed al-Sabah attends the inaugural session of the new parliament in Kuwait City. (YASSER AL-ZAYYAT / AFP)

KUWAIT - Sheikh Nawaf Al-Ahmad Al-Jaber Al-Sabah took his oath before the National Assembly on Wednesday to become the 16th emir of Kuwait.

Sheikh Nawaf Al-Ahmad Al-Jaber Al-Sabah was named the new Kuwaiti emir after the death of Sheikh Sabah Al-Ahmad Al-Jaber Al-Sabah, the Kuwaiti government announced on Tuesday evening after an extraordinary meeting.

Sheikh Sabah Al-Ahmad Al-Jaber Al-Sabah, the former emir, died on Tuesday aged 91, plunging his country into mourning for a leader regarded by many Gulf Arabs as a savvy diplomatic operator and a humanitarian champion

Nawaf, 83, pledged to work for the OPEC member country’s prosperity, stability and security after taking the oath of office, raising both hands to his head as lawmakers applauded.

“Our dear nation today faces difficult situations and dangerous challenges that can only be overcome ... by unifying ranks and working hard together,” he told the National Assembly.

The Constitution guaranteed smooth transition of leadership to ensure stability and sustainability, Nawaf said, vowing to carry out his responsibility to his utmost best and reiterating commitment to the constitution and democracy.

The former emir died on Tuesday aged 91, plunging his country into mourning for a leader regarded by many Gulf Arabs as a savvy diplomatic operator and a humanitarian champion

Sheikh Sabah had ruled the wealthy oil producer and US ally since 2006, and steered its foreign policy for more than 50 years.

The emir’s body will arrive on Wednesday in Kuwait from the United States, where he had been in hospital since July following surgery in Kuwait that month, state media reported on Tuesday, citing the Amiri Diwan.

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The minister of the Amiri Diwan said on Tuesday that in compliance with safety and public health requirements, the burial ceremony for the deceased emir will be limited to relatives only, state media reported.

The emir of Qatar, which has been boycotted by Saudi Arabia and its allies in a dispute that Sheikh Sabah tried until his death to resolve, will attend the funeral, state media said.

Flags were flying at half-staff in Kuwait, which announced 40 days of mourning. “Goodbye, Emir of Humanity,” read a large banner on a street near the Kuwait Stock Exchange. Kuwait Towers, a seaside landmark normally lit at night, went dark.

Condolences poured in from Arab leaders and several countries in the region announced mourning periods.

Sheikh Sabah sought to balance relations with Kuwait’s bigger neighbours - forging close ties with Saudi Arabia, rebuilding links with former occupier Iraq and keeping open dialogue with Iran.

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Iranian Foreign Minister Mohammad Javad Zarif, in an Arabic-language tweet, lauded Sheikh Sabah for fostering “moderation and balance” in Kuwait and the region.

“Today we lost a big brother and a wise and loving leader ... who spared no effort for Arab unity,” said Jordan’s King Abdullah, also on Twitter.

Sheikh Sabah kept strong ties with the United States, which led a coalition that ended Iraq’s 1990-91 occupation of Kuwait and used the Gulf state as a launch pad for the 2003 Iraq invasion.

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US President Donald Trump said in a statement he was saddened by the death of a dear friend and called Sheikh Sabah an “unwavering friend and partner to the United States”.

Trump earlier this month awarded the US Legion of Merit, Degree Chief Commander, to Sheikh Sabah in what the White House said was the first time the honour has been given since 1991. The emir’s eldest son, Sheikh Nasser, accepted the award.

United Nations Secretary-General Antonio Guterres praised the emir as “an extraordinary symbol of wisdom and generosity, a messenger of peace, a bridge builder.”

The Kuwaiti dinar fell against the dollar in the forward market on Tuesday and Kuwaiti stocks plunged, ahead of the official announcement of the emir’s death.

Under Kuwait’s constitution, the crown prince automatically becomes emir but assumes power only after taking an oath in parliament, for which elections are due this year.

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“I don’t see a major change in foreign policy under the new emir, largely because Kuwaiti foreign policy is pretty popular domestically and regionally and is seen as effective,” Courtney Freer, research fellow at LSE Middle East Centre, told Reuters.

The succession is not expected to affect oil policy or foreign investment strategy through the Kuwait Investment Authority, one of the world’s biggest sovereign wealth funds.

In this file photo taken on October 30, 2018 Kuwait's Emir Sheikh Sabah al-Ahmad al-Sabah gestures upon his arrival at the opening ceremony of the new legislative year in Kuwait City. (YASSER AL-ZAYAT / AFP)

The new emir’s choice of crown prince and premier - who would be tasked with managing the government’s often difficult relationship with parliament - will be watched closely.

“The new Emir will accede to the throne facing several tough challenges, including the coronavirus crisis, low oil prices, and delicate foreign politics,” London-based Capital Economics said in a research note.

An immediate priority would be a long-awaited debt law allowing Kuwait to tap global markets to finance a budget deficit, it said. Parliament, which analysts say has posed an obstacle to reform efforts, has repeatedly rejected the law.

Although most political power in Kuwait is in the hands of the emir, its parliament is one of the most influential elected bodies among Gulf monarchies.