The Congress on December 22 lost its status as the main opposition party in the Telangana Upper House after four of its members in the Legislative Council defected to the ruling TRS.
The four Congress MLCs defected to the TRS on December 21 and were promptly recognised by the Legislative Council chairman as members of the ruling party.
The Congress has a total of six members in the 40-member council.
At least two-third members of a legislature party are required to split it without attracting the provisions of the anti-defection law.
The Congress lost its opposition status in the council as one-tenth of the total strength of the House is required to enjoy the status.
"Hon'ble chairman Telangana Legislative Council hereby cancel the recognition of Sri Mohd Ali Shabbir MLC as the leader of the opposition in the Telangana legislative Council with effect from 22 December 2018," the notification said.
Meanwhile, TRS MLC Konda Murali said he tendered his resignation to the Chairman.
Murali's wife had unsuccessfully contested in the recently held Assembly polls.
The couple had defected to the Congress from TRS before the elections.