New Delhi zoo has temporarily closed after two birds died of bird flu, its curator said Wednesday, a month after India declared itself free of the disease.

Riaz Khan said tests had confirmed the birds died of the H5 strain of avian influenza, commonly known as bird flu.

"We have shut the zoo down only for two to four days to conduct tests and monitor the situation to see it does not spread," Khan told AFP.

He said a total of nine birds, including ducks, pelicans and painted storks, have died in recent days but only two were confirmed as having had avian flu.

"But in any case, the zoo has been closed as a precautionary measure and will reopen in a few days," he said.

The closure comes a month after India announced the country was bird flu-free, saying there had been no reports of an outbreak since May when more than 100,000 chickens were ordered to be culled in southern Karnataka state.

The zoo was in the spotlight in May after 46 spotted deer reportedly died of rabies.

In 2012, it had to close the rhinoceros enclosure after one of them died of suspected anthrax. But samples later tested negative.

Most strains of bird flu do not usually infect humans, according to the World Health Organization. But the H5 strain of the virus -- found in the zoo's birds -- can cause fever, cough, sore throat, pneumonia, respiratory disease and sometimes death.