Bangalore:  Former ISRO Chairman G Madhavan Nair on Monday said he would file an appeal under RTI by tomorrow seeking reasons for blacklisting him from government jobs even as he reposed faith in Prime Minister Manmohan Singh to revoke his ban order.

"I will file the appeal today or tomorrow (before the Central Information Commission)," he said here.

The Department of Space last week declined to reveal to him the specific recommendations and reasons for banning him from government jobs for his role in the controversial Antrix-Devas deal, and the factors taken into consideration.

The DoS cited Section 8 (1) (h) of the RTI, for not providing this required information, saying further enquiry is likely and divulging those details would impede investigation.

Asked about the Prime Minister not replying to his letter written soon after the ban order, Nair said his guess was that Singh would probably have asked the DoS to seek the opinion of the Law Ministry in the matter.

Noting that the Law Ministry's advice was known last week, he said, "Logically, it (the advice) may be presented to him and he (the Prime Minister) might take a decision on the matter. That's what I expect".

The ministry has told DoS to allow the four ISRO scientists "post decisional opportunity" to place their stand on its move debarring them from occupying any government position in future in the aftermath of the Antrix-Devas deal.

In an opinion to DoS, the ministry has also said no further probe into the deal is required and that there was no need for a charge-sheet at this stage.

Nair, who along with three other scientists have been barred from holding government posts for their role in the Antrix-Devas deal, said the entire scientific and legal community has expressed the view that the action against them was "illegal".

"Naturally subsequent steps should be to annul the (ban) order which (however) is not happening and I don't know why it's taking so much time.

"I have to fight it out. It's not only for my honour but it's the honour of entire scientific community. I have to fight it out till the last bit," he said.

Nair said "some strong pressure from some quarters" was responsible for annulment of the Antrix-Devas deal. After December 2009, there was no transparent reviews and no internal discussions vis-a-vis the deal and "everything was kept under the carpet and many of the information was kept

"Still they were taking drastic measures to cancel the contract which was about to mature. So, this can only happen if there is some strong pressure from some quarters".

 He said DoS' argument that the deal was cancelled because of procedural violations and also that S-band resources were needed for defence applications was "outright bluff".

"A series of bluffs and finally a decision is taken to cancel the contract," Nair said. "There are indications of some foul play from some quarters".

By cancelling the contract, India lost a golden opportunity, he said. "Just like DTH revolution that we brought in, we would have brought in hand-held (mobile) revolutions using satellites (had the deal been implemented). That's a big loss to the country, technically."