With 18 seats in parliament, she knows the government is dependent on her - and has been trying to use her position of power to maximum effect.

Jayalalitha: Made repeated demands of BJP

Since the BJP-led coaltion government came to power just over a year ago, Jayalalitha has threatened to withdraw support several times.

Her AIADMK party (All India Anna Dravida Munnetra Kazhagam) is the second largest in the coalition, and considered crucial to the government's survival.

Jayalalitha has used her position of influence to demand key posts for her ministers and the dismissal of others. In particular, she wants the state government in her home state, Tamil Nadu, to be sacked.

The BJP accuses her of being mercenary, and says her demands are an attempt to evade prosecution for alleged corruption during her days as chief minister in Tamil Nadu.

Glamour days

During her five years in power in Tamil Nadu, Jayalalitha developed an extravagant cult of personality.

Huge cutouts of her figure dominated the Madras skyline, ministers prostrated themselves at her feet, and her supporters almost worshipped her.

Her arrest on corruption charges three years ago was accompanied by the seizure of 64lb of diamond-studded gold jewellery, more than 10,000 saris and 750 shoes.

She also attracted international attention for the lavish wedding she organised for her foster son, alleged to have cost many millions of dollars.

For her current three-day trip to Delhi, she was reported to have sent ahead 48 suitcases.

Acting up

Her political acuity and taste for the high life can be traced back to her past career as an actress in Tamil-language films.

She played opposite MG Ramachandran, the biggest star in south Indian cinema - who also became an enormously successful politician.

The two developed close personal ties. On his death, she managed - after a battle - to succeed as his political heir.

Two years ago, her political career appeared to be over when her state government suffered one of the biggest landslide defeats India has ever seen.

She lost her own seat in the state assembly.

But in the general election last year, she bounced back - and now seems determined to bring down the Indian Government.