India's minister for water resources and river development, Uma Bharti, has announced government efforts to revive the Saraswati, a river that straddles the area between myth and reality.

The Saraswati is believed by many to have flowed from the Himalayas through northern India around 5,000 years ago, before drying up.

The river is mentioned in texts from the Vedic period, and experts have established traces of an ancient river system which matches some attributes of the Saraswati.

Imagery from the Indian Space Research Organisation (Isro) has shown a number of fossil valleys in the northern region of Haryana, corresponding to archaeological sites which suggest ancient settlements along the bank of a river. Meanwhile geological and glaciological studies have traced the route of a river through the plains of Haryana, Punjab, Rajasthan and Gujarat.

However it has been claimed by some that the river never existed at all, and was merely a myth.

Bharti told reporters there is sufficient scientific evidence to indicate the Saraswati did indeed exist, adding that the government has begun work "to trace the route of the river", with the ultimate aim of reviving it.

Experts like Umesh Chandra Chaube, professor emeritus of water resource development and hydrology at the Indian Institute of Technology Roorkee, have rubbished Bharti's project, saying that reflooding an area is impossible.

Professor Roger Evans, a hydrology expert at Virginia Tech University in the US, even suggested that reflooding the Saraswati would be the equivalent of putting a man on the Mars.