State-run refinery Hindustan Petroleum Corp Ltd, which runs a 150,000-barrels-per-day refinery in Andhra Pradesh, and Chennai Petroleum Corp Ltd , which can process 210,000 barrels per day from two plants in neighbouring Tamil Nadu, are also on alert.

But the weather office said the cyclone was unlikely to have an impact on the monsoon rains, vital for India's trillion-dollar economy which has been hit by high food prices, partly because of last year's poor rains.

Heavy rains

Heavy rains and lightning have already killed 10 people in Andhra Pradesh, prompting authorities to block public access to popular beaches and dispatch relief and rescue teams to vulnerable areas.

"Sea condition will be high to phenomenal along and off Andhra Pradesh coast and very rough along and off north Tamil Nadu coast," the weather office said in its latest forecast.

Pranav Choudhary, the chief financial officer at the Gangavaram Port, a coal-importing hub in Andhra Pradesh, said ships would take precautions during the storm.
   
A spokesman for Reliance Industries, which operates India's biggest gas field off the Andhra Pradesh coast, said the company was monitoring the situation.
   
Reliance's gas field has a capacity to pump 80 million cubic metres of natural gas, or about half of India's total output.

The cyclone is forecast to move towards Orissa after striking Andhra Pradesh, but it is likely to weaken by the time it reaches the Paradip port, a hub for iron ore exports.