National Award-winning film editor and screen-writer Apurva Asrani is unhappy with actress Kangana Ranaut for apparently claiming that she has co-written the script of the upcoming film 'Simran'.

Besides starring in the Hansal Mehta directorial, Kangana Ranaut has been credited as "additional dialogue and story" writer in the film's poster.

In a lengthy post on Facebook on Wednesday, Asrani said it was "demeaning for any writer's name to be pushed after an additional writing credit".

He said he was not offended by the credits, rather feels "betrayed" by Kangana.

"Ranaut has been claiming in several interviews that Hansal Mehta, the director of Simran', approached her with just a one line screenplay of the film. She says the story was dark and gritty thriller at that stage and that she herself developed it into a light, fun film," Asrani wrote.

"This completely discredits me and my efforts, and I have to call out this lie at the cost of so many of her fans turning against me. Those that know me will know that I have always strived for the truth and that is more important to me than a hit film," he added.

Asrani shared that Mehta sent him a news article of a woman in the US who crossed the line of the law.

"I loved it and thought it would make a great film. But I didn't want to do a serious film after Aligarh'. As gratifying as the experience of making Aligarh' was, it churned my insides out and left me emotionally drained. I saw 'Simran' as an opportunity to have some fun. This was two years ago," Asrani said.

Asrani said that both Kangana and Hansal gave him valuable inputs while he incorporated some and rejected the others.

"They were always happy with the outcome... At no point (during nine drafts and one and a half year) was there any talk or communication that Kangana didn't like the tone or direction of the script. In fact she used to jump with glee when I finished my narrations," Asrani said.

Asrani said that things got bitter the day after he "finished the first cut of the film" and Mehta informed him "nervously that Kangana is turning director and therefore has demanded a co-writer credit".

"I naturally had a shit fit and feeling shocked and betrayed. I refused to give in... I finally gave into an additional writing credit, but only because they claimed their film would be stuck if I didn't do so. But I refused to give her a co-writer credit, and we signed a letter where they promised me the same," he added.

Asrani says he can't understand "why Kangana would snatch the hard earned work of a writer".

"I wish she had been graceful about this and acknowledged what I brought to this film. I also wish that my dear friend Hansal shows some spine and either refutes or endorses my story," he said.

'Simran' is slated to release on September 15.