Delhi Police Commissioner B S Bassi also dismissed suggestions that police had been lax in collecting evidence and that the probe should be handed over to CBI, asserting that the force was "competent" to handle the case.
"The forensic report is inconclusive. The status of our inquest is pending," Bassi said.
"The first thing I would like to tell you is that we still do not have a conclusive forensic report on the basis of which we can reach on any conclusion. As far as police is concerned our inquest is pending.
"Whenever we will reach on any conclusion, when we get complete forensic evidence, conclusive evidence, then we will draw conclusion and then we will be able to share any information with you," the Delhi police chief told reporters here.
The 12-page "Subsequent Medical Board Opinion", submitted to police on September 30 by a panel of AIIMS doctors, said that the medical board had again concluded like it did in its first report that her brain, kidney, lungs and liver were functioning normally and that her death was caused by poisoning.
The new report by the three-member panel of doctors, who had conducted the autopsy on her, was prepared on the basis of the findings of the Centre Forensic Science Laboratory (CFSL) which had examined Sunanda's viscera.
Asked whether the Delhi Police will now register an FIR in this connection, he said, "Inquest is pending, once inquest is complete and we reach any definite conclusion. Whatever is required will be done and whatever is required to be shared with the press will be shared."
On suggestions whether the case should be transferred to CBI, Bassi said that the Delhi Police is "competent" to carry out the probe.
Responding to the allegations made by the panel of doctors that the investigating officer did not have photographs of scene of occurrence, statements and other circumstantial evidence in the case, which has been considered as laxity on the part of the police, Bassi only said, "We believe in quest for truth and whatever is required in the quest for truth we have been doing and we will continue doing".
The viscera report of CFSL in March had hinted at drug poisoning but police considered it as inconclusive. Police then asked AIIMS to re-examine the report and give its findings.
Police may now seek another expert opinion from the Central Forensic Science Laboratory (CFSL) or go for advance forensic tests to clear the air, according to sources.
Sunanda was found dead in a 5-star hotel in South Delhi on the night of January 17, a day after her Twitter spat with Pakistani journalist Mehr Tarar over an alleged affair with Tharoor.
The probe into the case was handed over to the Crime Branch on January 23. However, the case was transferred back to the South District police two days later on January 25.

Tharoor declines to comment
Former union minister Sashi Tharoor declined to comment on the fresh report by AIIMS doctors on the mysterious death of his wife Sunanda Pushkar that concluded she died of poisoning.
The Congress MP and former Minister of State for HRD, who was the chief guest at the graduation day function of a college here, avoided answering any query by persistent mediapersons.
Earlier during his speech at the function at the DG Vaishnav College, he said students awaited hard roads as challenges ahead in their lives.
"But you should believe in yourself, you should believe in the truth. I have been on those hard roads and that was the only way I was able to cope as well," he said.
Though the reporters attempted to elicit a response from him as he came out after the function, he didn't utter a word.

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