Opposition news reports have suggested that Mr Karimov, 78, has died.
He has led the former Soviet republic since before independence in 1991.
On Sunday, the Uzbek government said Mr Karimov was receiving treatment but did not give details.
The next day, the president`s daughter said he had suffered a brain haemorrhage.
In the past, the president`s health has been treated like a state secret, the BBC`s Abdujalil Abdurasulov says, and this week`s statements are the first time the government has provided information on the subject.
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