"The situation is very serious," said General Damdinsuren, deputy chief of the Mongolian State Emergency Commission, adding that the fire damage was "huge".
Smoke from about 80 fires across a sprawling country the the size of western Europe was hampering efforts to extinguish the blazes that had killed at least one woman.
"We cannot even see where and how large the fires are from the airplanes because every place is thick with smoke," said Mr Damdinsuren.
Since the fires roared onto the Mongolian Steppe on 9 April, some 3,000 firefighters, helped by nomads, have been working around the clock to bring the flames under control.
Shortages of food, exhaustion and poor equipment hampered firefighting efforts, Mr Damdinsuren said, adding that nomads in the remote Hentii mountains had fought the fire for days with just coats and tree branches.Reuse content