A top Indian scientist said Saturday he had resigned from the nation's Space Commission to protest the government's blacklisting of four scientists over alleged irregularities in a satellite deal.

The resignation by Roddam Narasimha, 78, from the highest space policy-making body in India is the latest development in a controversy that has rocked the top echelons of the country's scientific establishment.

Narasimha, who sent his resignation to Premier Manmohan Singh, said the treatment of the scientists could "demoralise" the nation's scientific community.

"I have requested the prime minister to permit me to relinquish my membership of the Space Commission," Narasimha, the longest-serving aerospace scientist on the commission, said in a statement.

The Space Commission directs the nation's space programmes and monitors projects of the Indian Space Research Organisation (ISRO) that have included the 2008 landing of a lunar probe on the moon's surface.

Narasimha objected to the treatment of the four scientists barred last month from holding any government office.

The government took the action against the scientists in connection with a 2005 deal between ISRO's commercial wing, Antrix Corp, and a private company, Devas Multimedia, to lease satellite radio wave space.

The government last year scrapped the $300-million contract amid allegations ISRO allocated the spectrum without following a proper bidding process -- a move media reports say could have caused large losses to the exchequer.

A government report said there had been "collusive behaviour on the part of certain individuals," in connection with the contract, but it made no suggestion that the individuals received any kickbacks or favours.

The four scientists blacklisted over the deal include former ISRO chief G. Madhavan Nair, who has described the government order as "discriminatory and unfair" and said: "We are being treated worse than terrorists.

In his resignation statement, Narasimha said the actions against the scientists "could demoralise the ISRO scientific community and adversely affect its ability to take the kind of technological initiatives... that are the hallmark of an innovative organisation.

The other three to be blacklisted were K.R. Sridhara Murthi, A. Bhaskar Narayana and K.N. Shankara.

The allegations involving allocation of satellite spectrum by the space agency come as Premier Singh's government is already grappling with a mobile telecom licensing scandal that may have cost the treasury up to $39 billion.

Singh holds overall charge of the Department Space.