The animal health department said in a report that tests showed H5N1 had killed ducks in the province of Soc Trang, just a day after bird flu was found in neighbouring Tra Vinh province.
The agriculture ministry has ordered an additional poultry vaccination campaign in the rice-growing region and requested reinforcement of animal health teams to contain the virus’ spread.
The ban on backyard fowl in Indonesia - with 61 deaths from bird flu, a third of the world’s total - will first be imposed in the capital, Jakarta, and neighbouring provinces of West Java and Banter, which are highly prone to the H5N1 virus, Aburizal Bakrie, a government minister, said.
Millions of Indonesian chickens live in close proximity to humans and the ban could be difficult to enforce.
The minister did not say when the ban would be imposed, but said the appropriate ministries would help direct provincial governments on how to implement it.
Meanwhile, the authorities in southern Japan have begun incinerating about 12,000 chickens hit by the H5N1 virus in Kiyotake.
Japan has confirmed one human case, but reported no human deaths.
Since 2003, the H5N1 bird flu strain has killed at least 157 people worldwide, according to the World Health Organisation.