The United Arab Emirates' long-ailing ruler, Sheikh Khalifa bin Zayed Al Nahyan, died Friday, the government announced in a brief statement. He was 73.
Khalifa, the president of the UAE, oversaw much of the country's blistering economic growth and his name was immortalized on the world's tallest building, the Burj Khalifa, after bailing out debt-crippled Dubai during its financial crisis over a decade ago.
The UAE's Ministry of Presidential Affairs announced a 40-day period of mourning and a three-day suspension of work across the government and private sector, including flags to be flown at half-staff. An outpouring of messages of condolences poured in from around the region and world, foremost the leaders of Arab countries supported by Abu Dhabi.
Sheikh Khalifa had long ceased having involvement in the day-to-day affairs of ruling the country after suffering a stroke and undergoing emergency surgery in 2014, a decade after becoming president.
His half-brother, Abu Dhabi Crown Prince Mohammed bin Zayed, was seen as the country's powerful de-factor ruler and the decision-maker of major foreign policy decisions, such as joining a Saudi-led war in Yemen and spearheading an embargo on neighboring Qatar in recent years.
There was no immediate announcement about a successor, although Mohammed bin Zayed is anticipated to claim the presidency as Abu Dhabi's crown prince.
Sheikh Khalifa's father, Sheikh Zayed bin Sultan Al Nahyan, is widely revered by Emiratis as the country's founding father. The country was founded in 1971, having recently marked its 50-year-anniversary. Sheikh Khalifa, trained at Sandhurst, the royal military academy in England, was his eldest son.
Though he had been out of public sight since the stroke, Sheikh Khalifa's image was ubiquitous, gracing every hotel lobby and major government office across the country. On occasion, Emirati state media published rare photographs and videos of Sheikh Khalifa.
'The UAE has lost a loyal son, and the leader of its blessed empowerment journey, ' Sheikh Mohammed bin Zayed wrote on Twitter after news of his brother's death was officially announced on state media. 'Khalifa bin Zayed, my brother, supporter and mentor, may Allah Almighty grant you eternal peace.'
FILE - President of the United Arab Emirates Sheikh Khalifa bin Zayed Al Nahyan arrives at Clarence House in central London, May 1, 2013.
The late president held the most powerful position among the seven semi-autonomous city-states stretching along the shores of the Persian Gulf and the Gulf of Oman. His role as president derived from his standing as hereditary ruler of Abu Dhabi, the UAE's largest and richest emirate.
Historically, the president of the UAE is from Abu Dhabi and the vice president and prime minister is from Dubai, currently Sheikh Mohammed bin Rashid Al Maktoum.
The UAE's regional power and influence, however, emanates from Abu Dhabi, which has most of the country's oil and gas reserves. Dubai provides the UAE with a swirl of publicity and headline-grabbing lifestyle and entertainment stories that rights groups say distracts from controversial policies decided in Abu Dhabi.
Despite its size and wealth, Abu Dhabi often finds itself overshadowed by the glitzy emirate of Dubai, the commercial hub that showcases both the UAE's bold visions and, at times, debt-fueled pipe dreams, including a massive palm-shaped man-made island that sits empty years after its creation.
As Dubai's fortunes began to falter along with the global economy in 2009, Sheikh Khalifa led efforts to protect the federation by pumping billions of dollars in emergency bailout funds to Dubai. The two emirates do not always see eye-to-eye on foreign policy decisions and compete commercially with one another. In 2003, Sheikh Khalifa ordered the creation of a new airline, Etihad Airways, which competes with Dubai's much larger Emirates Air.
Khalifa increasingly used Abu Dhabi's oil wealth to attract cultural and academic centers, such as a branch of the Louvre museum and satellite campuses of New York University and the Sorbonne. He also presided over efforts to move the OPEC country beyond its reliance on petrodollars with investments in renewable energy research, including a vision for a futuristic low-carbon desert city known as Masdar. The UAE announced last year a net-zero emissions pledge by 2050, even as it expands investments in oil and gas for export.
FILE - Sheikh Khalifa bin Zayed Al Nahyan, the president of the United Arab Emirates and ruler of Abu Dhabi, right, is greeted by Sheikh Mohammed bin Zayed Al Nahyan, the crown prince of Abu Dhabi, center, at Al Bateen Palace in Abu Dhabi, United Arab Emirates, May 8, 2019.
Abu Dhabi's big spending overseas during Khalifa's rule helped shape its investment strategy. The Abu Dhabi Investment Authority is now one of the world's largest sovereign wealth funds with close to $700 billion in assets, according to estimates by the Sovereign Wealth Fund Institute.
Khalifa also helped boost the UAE's regional profile by sending warplanes to the NATO-led mission against Moammar Gadhafi's regime in Libya in 2011. In September 2014, the Emirates became one of the most prominent Arab participants in U.S.-led airstrikes against the Islamic State militant group in Syria, deploying its first female air force pilot on the initial raid.
Khalifa was born in 1948 in the inland oasis of Al Ain, near the border with the sultanate of Oman, and named after his great grandfather, Sheikh Khalifa bin Shakhbout.
In 1969, while the area was still a British protectorate, Khalifa was named as Abu Dhabi prime minister and chairman of the emirate's Department of Defense, which later became the core of the UAE's armed forces. After independence in 1971, he became defense minister.
Although the UAE's ruling sheikhs hold near absolute power, Khalifa began an experiment with elections by allowing limited voting - by a hand-picked electorate - for half the members of a 40-seat federal advisory body in 2006. Subsequent rounds of elections in 2011 and 2015 failed to attract even two out of five of those given a chance to vote.
The UAE saw none of the Arab Spring street protests that shook other parts of the region, though in the wake of that unrest, Khalifa oversaw crackdowns on Islamists and other activists in the country, drawing criticism from international rights groups. The UAE, which views Islamist movements as a threat to its ruling system, also supported efforts in the region to quash the Muslim Brotherhood, including in Egypt.
FILE - In this image made available by Emirates News Agency, WAM, UAE President Sheikh Khalifa bin Zayed Al Nahyan, 2nd right, walks with Saudi Arabia's Prince Nayef bin Abdul Aziz during the 31st Gulf Cooperation Council, GCC summit in Abu Dhabi, Dec. 6, 2010.
Under his presidency, the UAE joined Saudi Arabia in sending forces to Bahrain to quell an uprising there by the country's majority Shiite population demanding greater rights from the island-nation's Sunni leadership.
Questions were raised during Khalifa's rule about the UAE's use of foreign military contractors, including one linked to the founder of the former Blackwater security firm, Erik Prince, who moved to Abu Dhabi in 2009. Prince was involved in a multimillion-dollar program to train troops to fight pirates in Somalia, according to an official who spoke to The Associated Press in early 2009.
A U.S. diplomatic cable made public by WikiLeaks in 2010 uncharitably described the president as 'a distant and uncharismatic personage.' The final years of his presidency are likely to be associated with his half-brother, Mohammed bin Zayed, who is also the deputy supreme commander of the armed forces and who has shepherded the UAE's budding ties with Israel after the two normalized relations in 2020.
Sheikh Khalifa was believed to be among the world's richest rulers with a personal fortune estimated by Forbes magazine in 2008 at $19 billion. He built a palace in the Seychelles, an island-chain nation in the Indian Ocean, and faced complaints there about causing water pollution from the construction site.
Khalifa's personal life was not much in the public eye. Like many in the Gulf, he was passionate about the traditional sport of falconry and was said to enjoy fishing. He is known to have had eight children - two sons and six daughters - with his first wife, Sheikha Shamsa bint Suhail Al Mazrouei. He is also survived by several grandchildren.