India's wrestling federation was on Wednesday appealing the disqualification of star athlete Vinesh Phogat at the Paris Olympics after she failed to make weight for the women's 50kg final.

World bronze medallist Phogat, 29, was in the public eye for months last year as part of a long-running protest against the then-chief of Indian wrestling when he was embroiled in a sexual harassment scandal.

She was due to face Sarah Hildebrandt of the United States for the gold medal but was found to be overweight for her category.

The Wrestling Federation of India (WFI) had filed an appeal with global governing body United World Wrestling to reconsider the decision to disqualify Phogat.

"Despite the best efforts by the team through the night, she weighed in a few grams over 50kg this morning," the IOA said in a statement.

IOA president P.T. Usha said Phogat's disqualification was "very shocking", adding that the team was providing Phogat with "all medical and emotional support".

Phogat was considered a strong prospect for winning gold at her third Olympic appearance and her sidelining was greeted with shock at home.

"I wish words could express the sense of despair that I am experiencing," Prime Minister Narendra Modi said in a social media post.

"Come back stronger! We are all rooting for you."

Phogat helped lead a weeks-long sit-in protest in New Delhi last year against then-WFI chief Brij Bhushan Sharan Singh, at the time a lawmaker from Modi's ruling party.

Singh is being tried on accusations of groping female athletes and demanding sexual favours from them -- charges he denied.

Wrestling is hugely popular in rural northern India and images of Phogat and other athletes being detained as they tried to march to parliament during the protest went viral on social media.

"Vinesh you are a gold medallist of courage and morality," Bajrang Punia, a fellow leader of last year's protests, and a Tokyo Olympics bronze medallist, said on social media.

"You have fought with grit," he added. "Nobody wants to believe what happened this morning."