More than 1,100 people have died in a blistering heatwave sweeping India, authorities said Wednesday, as forecasters warned searing temperatures would continue.

Southern India has borne the brunt of the hot, dry conditions and many of the victims are construction workers, elderly or homeless people unable to heed official advice to stay indoors.

In the worst-hit state of Andhra Pradesh nearly 900 people have died since May 18 -- double the total number of heat-related deaths last summer, authorities said.

In neighbouring Telangana, where temperatures hit 48 degrees Celsius (118 degrees Fahrenheit) over the weekend, more than 200 people have died in the last week compared to 31 in the whole of last year.

In New Delhi, forecasters said they expected the high temperatures to continue into next week -- adding to the misery of the thousands of poor living on the capital's streets with little shelter from the hot sun.

Residents of Gurgaon -- a high-rise satellite city that is home to many of the capital's workers -- suffered power cuts of up to 10 hours a day as the electricity grid struggled to cope with the demand from millions of air conditioners.

"Nothing is working -- even after taking half a dozen baths a day, you can't beat the heat," 34-year-old shop owner Manish Singh told AFP in Gurgaon.

"We try to spend more time indoors to avoid heatstroke. It's worse than previous years -- we hardly get any electricity and the air conditioners become useless."

More than 9,700 people died between 2004 to 2013 due to heat strokes, according to National Crime Records Bureau (NCRB).

The NCRB shows in 2012 nearly 1,250 people died across India, while scorching temperatures killed more than 1,200 people the following year.

India's power industry has long struggled to meet rapidly rising demand in Asia's third-largest economy, which is plagued by poorly-maintained transmission lines and overloaded grids.

- No respite from heat -

The streets of Gurgaon were largely deserted on Wednesday, while the few people brave enough to venture outdoors covered their heads to protect them from the strong sun.

Sugarcane juice stalls were doing a brisk trade as construction workers and rickshaw pullers desperately tried to quench their thirst. Elsewhere volunteers were giving out cold drinks to motorists stuck in traffic.

Brahma Prakash Yadav, director of the Indian Meteorological Department, said top temperatures in the capital would remain around 45 degrees Celsius -- the national benchmark for a heatwave.

"Maximum temperatures won't fall substantially. However, major relief can be expected from June 2 as there are indications of good showers," he said.

Hospitals in the worst-affected states were on alert to treat victims of heatstroke and authorities advised people to stay indoors and drink plenty of water.

Hundreds of people -- mainly from the poorest sections of society -- die at the height of summer every year across India, while tens of thousands suffer power cuts from an overburdened electricity grid.

Forty-three were reported to have died in the eastern state of Orissa, according to the Press Trust of India (PTI) news agency.

Another 13 succumbed to the heat in neighbouring West Bengal, where unions urged drivers to stay off the roads during the day.

One person was killed in neighbouring Maharashtra, where authorities said they did not expect conditions to improve until the arrival of monsoon rains in June, while PTI reported that seven more died in adjacent Gujarat.

The Hindustan Times newspaper warned that some of the hot, dry conditions could plunge the worst-affected states into drought before monsoon rains arrive.

The monsoon is forecast to hit the southern state of Kerala towards the end of this month before sweeping across the country, but it will be weeks before the rains reach the arid plains.