Uzbekistan's President Islam Karimov is critically ill, prompting speculation that Central Asia's most populous nation is preparing for its first transfer of power since independence.
The health of Mr Karimov, 78, has sharply deteriorated over the past 24 hours, the government said in a brief statement published by official newspaper Narodnoye Slovo.
"The doctors assess [his health] as critical," the cabinet said, adding that Mr Karimov has been in hospital since Saturday, when he suffered a stroke.
Several other media, including Russian news agency RIA and Uzbek news website Gazeta.uz, also ran reports quoting the same statement.
Mr Karimov has ruled Uzbekistan, a major cotton exporter also rich in gold and natural gas, in an authoritarian style since 1989, first as a Communist leader, and then as president, after the Soviet Union fell in 1991.