NEW DELHI (AFP) - An Indian court has ruled that the daughters of a late maharaja should inherit his 200-billion-rupee (S$4.28-billion) estate because his will was forged more than 30 years ago, lawyers said Monday.

The verdict in the northwestern city of Chandigarh ended a two-decade legal battle over the fortune of Maharaja Harinder Singh Brar, the ruler of the princely state of Faridkot who died in 1989.

Magistrate Rajnish Kumar ruled last Thursday that the will had been faked to award his vast property holdings and family heirlooms to a trust managed by one of his three daughters, his servants and lawyers.

"Since the will has been declared illegal... the legal heirs of rajasahib (maharaja) are entitled to the property," a lawyer quoted the magistrate as saying in his ruling.

The two surviving daughters of the ex-ruler, including the daughter who managed the trust set up under the forged will, are the legal heirs.

The maharaja's third daughter, Maheepinder Kaur, died in 2001.

"We have won the case after 21 years," Vikas Jain, a lawyer representing one of the daughters excluded from the will, Amrit Kaur, told AFP.

Amrit Kaur, who lives in Chandigarh, fought the battle against the "Meharwal Khewaji Trust" headed by her sister Deepinder Kaur who lives in the eastern city of Kolkata.

Media reports said the ruler was suffering from depression due to the death of his only son in a road accident when the will was purportedly fabricated by lawyers and his servants 32 years ago.

No one in his family was named as a direct beneficiary in the forged will.

His assets included forts, a palace, prime property in the capital, cash, jewellery and a 22-acre (nine hectare) private aerodrome in the city of Faridkot.

Brar was an enormously wealthy Sikh ruler of Faridkot before India's independence from Britain in 1947.

After independence, 565 princely states either merged with India or with Pakistan through separate treaties and agreements.

The Indian government in 1971 through a constitutional amendment discontinued the practice of doling out lavish privileges and money to royal families.

Many of them, after losing their opulent and glamorous lifestyles, have converted their palaces and forts into hotels to make a living.

However many royal families are still venerated by locals in their former kingdoms and they remain in possession of some of their palaces, forts and land.

The head of a former Indian princely family in 2011 renounced any personal claim to ancient treasure worth up to US$22 billion. It was discovered in a Hindu temple in the kingdom which his ancestors once ruled in the southern state of Kerala.