Government spokesman Major General Zaw Min Tun told state-run MRTV another 3400 people have been injured and more than 300 are missing.
The military had previously reported 1644 dead but did not provide specific figures in its update on Monday.
The earthquake hit at midday on Friday, causing widespread damage, including in the capital, Naypyidaw, and the second-largest city, Mandalay.
It was the time of Friday prayers for the country's Muslim minority during the holy month of Ramadan, and some 700 worshippers were killed when mosques collapsed, said Tun Kyi, a member of the steering committee of the Spring Revolution Myanmar Muslim Network.
It was not clear whether they were already included in the official count of casualties.
Tun Kyi said some 60 mosques were damaged or destroyed when the earthquake struck, and videos posted on The Irrawaddy online news site showed several mosques toppling during the quake, and people fleeing from the areas.
The true number of people killed and injured is thought to be possibly many times the official figures, but with telecommunication outages and extreme challenges to movement around the country, little is known about the damage in many areas.
"We're really not clear on the scale of the destruction at this stage," Lauren Ellery, deputy director of programs in Myanmar for the International Rescue Committee, told The Associated Press.
There is a state of emergency in six regions, and Ellery said her teams on the ground and their local partners are currently assessing where needs are the greatest, while providing emergency medical care, humanitarian supplies and other assistance.
A woman was freed from the ruins of a Mandalay hotel after 60 hours trapped under the collapsed Great Wall Hotel.
The rescue was a five-hour operation by Chinese, Russian and local teams, according to a Chinese embassy Facebook post. It said she was in stable condition early on Monday.
The earthquake, centred near Mandalay, a city of some 1.5 million, brought down buildings and damaged other infrastructure such as the city's airport.
The earthquake also shook neighbouring Thailand and killed at least 18 people, many at a construction site in Bangkok where a partially built high-rise collapsed.
Another 33 have been reported injured and 78 missing, primarily at the construction site near the popular Chatuchak market.
Bangkok governor Chadchart Sittipunt told reporters at the scene that signs of life had been detected on Sunday night, though experts could not determine whether it had been a machine error.
"Even if one life is saved, it is worth all the effort," he said.
The United Nations said it was rushing relief supplies to an estimated 23,000 quake-hit survivors in central Myanmar.
"Our teams in Mandalay are joining efforts to scale up the humanitarian response despite going through the trauma themselves," said Noriko Takagi, the UN refugee agency's representative in Myanmar.
India, China and Thailand are among Myanmar's neighbours that have sent relief materials and teams, along with aid and personnel from Malaysia, Singapore and Russia.
The United States pledged $US2 million ($A3.2 million) in aid "through Myanmar-based humanitarian assistance organisations".
The quake devastation has piled more misery on Myanmar, already in chaos from a civil war that grew out of a nationwide uprising after a 2021 military coup ousted the elected government of Nobel Peace Prize laureate Aung San Suu Kyi.
With Reuters
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