India has issued a fresh flood alert for parts of the southern state of Kerala, as the death toll from the annual monsoon deluge across the country rose to at least 209.

Authorities on Wednesday warned Kerala locals of heavy to extremely heavy rainfall over the next 24 to 48 hours in some of the worst affected regions of the state popular with tourists.

Heavy rains in parts of four Indian states - Kerala, Karnataka, Maharashtra and Gujarat - have forced more than 1.2 million people to leave their homes and take shelter in government-run relief camps.

In Karnataka, several structures at the world heritage site Hampi, an ancient town, were flooded.

Last year, Kerala was hit by its worst floods in almost a century, and is still recovering from the extensive loss of life and damage to public infrastructure including highways, railways and roads.

Around 450 people lost their lives there in 2018.

The death toll this monsoon season in the state increased to 95 overnight and at least 59 people were missing, Kerala police told AFP news agency on Wednesday.

At least 48 people have also lost their lives in neighbouring Karnataka state, where authorities have also rescued around 677 000 people from flooded regions.

Local media have also reported 66 deaths in the western states of Gujarat and Maharashtra, with hundreds of thousands rescued from inundated regions.

India has also deployed the army, navy and air force to work with the local emergency personnel for search, rescue and relief operations in the flooded regions.

The monsoon rains are crucial to replenishing water supplies in India, but they kill hundreds of people across the country every year.

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