New Delhi: Senior BJP leader Subramanian Swamy on Friday said that he will file Public-Interest Litigation (PIL) in Sunanda Pushkar murder case if Delhi Police will not make any progress in the case by January 17.

Taking to Twitter, Swamy wrote, “If by January17, the Delhi Police does proceed on Sunanda murder case – now that FBI has confirmed AIIMS Forensic Report – I will file a PIL.”

If by17th, the Delhi Police does proceed on Sunanda murder case--now that FBI has confirmed AIIMS Forensic Report--I will file a PIL. — Subramanian Swamy (@Swamy39) January 1, 2016

The Delhi Police in November had shared the findings of an FBI report that virtually rules out the theory of 'polonium poisoning' causing her death.

“Radiation levels in Sunanda Pushkar's viscera samples were "within the standard safety norms",” Delhi Police had said.

According to sources, the FBI report, received nine months after the samples were sent for examination, has named the alleged poison that led to Sunanda's death two year's ago.

The viscera samples were sent to the FBI lab in Washington in February to determine the kind of poison that killed her after an AIIMS medical board identified poisoning as the reason behind her death but did not mention any specific name.

Reacting to the developments, AIIMS forensic head Sudhir Gupta stuck to his opinion that poisoning was the cause of death.

Sunanda was married to Congress leader Shashi Tharoor at the time of her death.

(With PTI inputs)