New Delhi: Facing flak over declining revenues and market share, the chairman and managing director of state-run telecom service provider Mahanagar Telephone Nigam Ltd (MTNL) R.S.P. Sinha resigned on Tuesday.

No extension: Former MTNL chairman R.S.P. Sinha. He had been given an ad hoc extension in September, but failed to secure another. Ramesh Pathania / Mint

“Yes, I have put in my papers," said Sinha, who had been given an ad hoc three-month extension in September after his five-year term ended.

Central telecom minister A. Raja said Sinha’s tenure was over and he had not been given a further extension. Senior officials in the Department of Telecommunications (DoT) also said Sinha resigned after failing to secure another extension.

The resignation brings his contentious stint with MTNL, which operates in New Delhi and Mumbai, to an end.

Sinha’s September extension had been challenged in the Delhi high court. A petitioner had alleged it was against prevailing laws. He is also facing a legal battle over allegations that he unduly favoured Motorola Inc. in a Rs150 crore deal 10 years ago. He was then director of finance at MTNL.

The Central Bureau of Investigation (CBI) has asked to be allowed to close the investigation in this case due to lack of evidence. But a CBI special court denied this request.

Sinha’s resignation also comes amid a debate over the falling revenues and financial performance of the public sector undertaking.

MTNL has been suffering a steady loss of market share, especially in its fixed line subscriber base, and is also seeing profits being eaten up by a huge redundant employee base.

Sinha had gone to attend an MTNL board meeting on Monday, when he received a call from telecom secretary P.J. Thomas, asking him to step down, an official said on condition of anonymity. He left the venue even before the meeting started.