A trust named after Carnatic musician Irayimman Thampi has accused Bombay Jayashri's Oscar-nominated song 'Pi's Lullaby' of not being an original composition, an allegation denied by the vocalist.

The song, written and sung by Jayashri for the film Life of Pi, has been nominated in the Original song category at the Academy awards this year, but the trust has alleged that it is a word-by-word translation of composer Thampi's renowned lullaby in Malayalam "Omanathinkal Kidavo..."

Thampi (1782–1856) was the palace singer in the court of Swathi Tirunal Maharaja, the ruler and music legend of Travancore in the 19th century. Legend has it that Thampi composed the lullaby for the royal children.

According to Irayimman Thampi Trust chairman, N Krishna Varma and secretary Rukmini Bhai Thampuratti, descendants of Thampi, Jayashri's song was a "mere translation of the Malayalam verse into Tamil."

"Jayashri has copied the first eight lines of Irayimman Thampi's lullaby which has passed on to generations and is the greatest among the lullabies of the past, present and the future," Thampuratti told reporters at Cherthala.

Reacting to the brewing controversy, Jayashri has denied the charge against her and maintained that she only wrote whatever came to her heart.

"I can only say that I wrote whatever that came to my heart," Jayashri told PTI at her Chennai residence.

Jayashri is the only Indian nominated at the Oscars this year. The award ceremony is set to be held on February 24 in Los Angeles.

The Trust has threatened to take legal action against Jayashri if she did not come out with an explanation about her song and its striking similarity to Thampi's composition.

"We will not allow the copying of a song just for the sake of getting an award," Varma said.

They said they could not get through to Jayashri over the phone despite several attempts since yesterday.

The Trust is based at Naduvile Kovilakam at Cherthala in Alappuzha district, the ancestral home of Irayimman Thampi. The 156th death anniversary and the 229th jayanthi celebrations of the poet were observed recently.