French island group Mayotte will begin distributing bottled water to its 310,000 inhabitants this month as the region faces its worst drought episode this century, the government said Thursday.

The Indian Ocean archipelago, the lowest-income region in France with most people below the poverty line, depends on rain for its drinking water, but rainfall has been at its lowest since 1997.

France's minister for overseas territories Philippe Vigier told reporters each inhabitant would be entitled to one litre of bottled drinking water per day starting on November 20.

According to the European Food Safety Authority, two litres of water per day are considered an adequate intake for women, and 2.5 litres for men.

The archipelago has been facing severe water restrictions since September, and the government has already been supplying bottled water daily to the 50,000 most vulnerable inhabitants.

Preschools and primary schools will be the first to benefit from the additional water deliveries.

Mayotte's daily water needs are estimated at around 43,000 cubic metres, but supply is currently down to 26,000 on average.

This will drop to or below 20,000 cubic metres per day once the remaining reserves in Mayotte's artificial lakes run out.