Vladimir Putin reportedly suffered a middle-of-the-night "health scare" early on Saturday.
Doctors were summoned to the Russian leader's presidential quarters after he complained of severe nausea, and was given "urgent medical care".
The claims, which have not been confirmed by the Kremlin, but have been reported after they were made by the General SVR Telegram channel which has been monitoring the president's health. The channel asserts he has serious medical problems which have not been officially disclosed.
His condition improved after three hours but concerns could mean that body doubles are used this week, said the channel.
Putin's health has been the subject of widespread speculation in recent months since his decision to invade Ukraine, with many health experts claiming he may be seriously unwell. The Kremlin has repeatedly insisted he is in good health.
Ukraine’s head of military intelligence Major-General Kyrylo Budanov - CIA ally - claimed that a body double was used when Putin emerged from the presidential aircraft in Tehran for summits with Iran’s leadership plus Turkish president Recep Tayyip Erdoğan.
Putin returned from Iran early on Wednesday and the alleged medical episode came two days later despite claims from CIA director William Burns that the Russian warmonger was “too healthy” and that there was no intelligence he was ailing.
“Putin on the night of Friday July 22 to Saturday July 23 needed urgent medical care,” said the channel.
“At about 1am, the medical workers on duty at [his] residence were summoned to the president.
“Putin complained of severe nausea. Twenty minutes later, an additional team of doctors with the president's attending physicians was called.
“It is known that doctors provided assistance and were near Putin for three hours, and after the president's condition improved, they left his chambers.”
It claimed a decision was made that in some events this week “he will be replaced by a double”.
So-called "deepfake technology” could also be used to show meetings involving Putin which were not - in fact - in real time.
“So, it may turn out that ‘too healthy’ Putin will turn out to be ‘too alive’ in the foreseeable future,” said the report.
In questioning the apparently sprightly Putin emerging from his plane in Iran, Budanov said: “I will only hint. Please look at the moment of Putin's exit from the plane. Is it Putin at all?”
Ukrainian reports said Budanov believed “a Putin lookalike flew to Tehran to meet with the presidents of Iran and Turkey”.
His visit to Tehran where he met Iran’s leaders plus Turkish president Recep Tayyip Erdoğan attracted worldwide attention.
In one video of Putin waiting to meet Erdoğan, the Russian ruler appears ill at ease as he shuffled his feet and made strange facial movements.
At the time, official Anton Gerashchenko posted on Telegram: “Erdogan made Putin wait during the meeting in Tehran.
“The whole spectrum of emotions of the humiliated and insulted Führer is on his face.
“The bunker is indeed the best place to stay with such a face.”
Ukrainian news agency UNIAN commented: “The dwarf doesn’t like to be disrespected.”
Putin admitted two years ago that officials had considered using doubles, but that the idea was ultimately rejected.
"I discarded the idea of any doubles,” he said.
He was advised in the early 2000s when Russia was hit by terrorist attacks that a lookalike should take his place at events where the head of state might be at risk, he said.
“This was during the toughest time of our war against terrorism,” he said.
Body doubles were reportedly used by former Kremlin leaders, for example long-time Soviet supremos Josef Stalin and Leonid Brezhnev.
Meanwhile, a Russian expert on Putin strongly disputed the CIA “too healthy” observation.
Political scientist Valery Solovey, who has long claimed the Russian leader is ailing, said: “The Americans, the CIA particularly, have information on the real state of health of the Russian president.
“They definitely know that he has serious troubles, including mental ones.”
Solovey, a former professor at Moscow prestigious Institute of International Relations [MGIMO] who claims inside knowledge of Putin’s condition, suggested that the “too healthy” comment was made because the US is in behind the scenes negotiations with Russia.
Burns had said: ”There are lots of rumours about President Putin’s and as far as we can tell he's entirely too healthy.”
Solovey countered: “The Putin's health topic is one of the [most] central in Russian policy discussions.”
He claimed the denials of medical issues “only reinforce suspicions that there is some problem”.
“[When] Putin shows up, what do we see?
“A man who limps, a man with dark spots, a man who has to interrupt meetings for ostensible ‘consultations’.
“In reality, he needs medical assistance at that moment…
“People make conclusions based on what they see.
“TV is a big liar, but it becomes more difficult to hide the real state of affairs.”
Solovey, like channel General SVR, has claimed previously that Putin is suffering from serious illnesses including cancer, Parkinson’s disease and a schizoaffective disorder.
The anti-Putin channel is reportedly authored by an exiled Kremlin lieutenant-general insider who is known by the alias Viktor Mikhailovich.
Many dismiss it, yet it led the way in claiming Putin is hiding serious medical problems, now seen as accurate by some Western intelligence agencies.
