Top Indian Olympic wrestlers have criticised Prime Minister Narendra Modi's party for fielding the son of their former federation chief in national elections, despite his father being charged with sexually harassing female wrestlers.

Scores of Indian wrestlers came out in protest last year seeking criminal action against Brij Bhushan Sharan Singh, a lawmaker from Modi's Bharatiya Janata Party (BJP).

A trial court admitted a case of sexual harassment and intimidation against Singh, who has denied wrongdoing and is currently on bail.

In India's long general election, Singh's son Karan is standing as a BJP candidate in his father's Kaiserganj seat in the politically crucial Uttar Pradesh state, a seat Brij Bhushan Sharan Singh has previously won six times.

"Daughters of the country have lost, Brij Bhushan won," said Sakshi Malik, a 2016 Rio Olympics bronze medallist, in a social media post on Thursday. "By giving an election ticket to his son, they have shattered the aspirations of the country's millions of daughters."

BJP national spokespersons did not immediately respond to Reuters requests for comment.

Indians are voting in a seven-phase parliamentary election that began on April 19 and ends on June 1, with Modi widely tipped to win a third term when results are announced on June 4.

Malik quit the sport in protest last year and fellow Olympic medallist Bajrang Punia returned one of India's highest civilian awards.

Punia wrote on social media on Thursday: "It is the misfortune of the country that daughters who win medals will be dragged on the streets and the son of the person who sexually exploits them will be honoured by giving him a ticket."

Opposition Congress party spokesperson Jairam Ramesh said the BJP had fallen to a "new low" and had no "moral compass".

Awanish Tyagi, a state BJP spokesperson, dismissed the opposition criticism in his comments to ThePrint news website and said issues are being created "deliberately".