India's main airport in flood-devastated Tamil Nadu state reopened on Sunday as emergency workers strove to help thousands of residents forced to flee their inundated homes.

The international airport in the state capital Chennai had closed on Wednesday leaving thousands of passengers stranded, after record rains worsened flooding that has claimed nearly 300 lives since November 9.

"There was no damage to the runway. It remained under water for a few days but has been cleared now," national Aviation Minister Mahesh Sharma said as passengers started to gather at the terminal.

"We had a few relief flights yesterday from the airport and today commercial flights have resumed their services."

Thousands of residents have been rescued by boat or plucked from rooftops after the floods left much of Chennai, a city of more than four million, underwater. Power supplies and phone networks were also hit.  
Soldiers and other emergency workers who poured into the southeastern state have now switched to rushing food, clean drinking water and medical supplies to hard-hit residents.

"The army has... distributed relief materials including water and food to over 20,000 people," said Colonel Rohan Anand.

But rain was again falling in Chennai on Sunday, threatening to hamper relief efforts along with attempts to clear roads of waterlogged debris.

Anger is mounting among some residents who accuse local authorities of failing to work swiftly to help those affected.

V. Padmavathy said she had been stuck on the first floor of her home for days after waist-deep water swept through her north Chennai neighbourhood.

"None of the politicians or volunteers have approached us for the past couple of days. Many of us stayed indoors and starved," the mother of two told AFP.

Prime Minister Narendra Modi has described the floods as a consequence of climate change, as top negotiators meet in Paris to try to agree on reducing the rate of global warming.

Experts have said poor urban planning had likely worsened the disaster.

India suffers severe flooding every year during the annual monsoon rains from June to September.