The Telangana Assembly on Friday issued a notification stating that all the three legislators of YSR Congress Party have been "merged" with the ruling TRS.
YSR Congress has three legislators and one Lok Sabha member in Telangana. While two of its MLAs, T Venkateswarlu and Banoth Madan Lal, defected to TRS last year, P Venkateswarlu along with Khammam MP Ponguleti Srinivas Reddy quit the party and joined TRS two days ago.
The MLAs had submitted a letter to the Speaker stating they had merged with Telangana Rashtra Samiti Party (TRSLP).
Subsequently, the Speaker allotted them seats with the members of TRSLP in the House, a release from the Assembly said.
A number of MLAs from Opposition Congress, TDP and YSR Congress have joined TRS since it came into power in 2014.
Terming the Speaker's act as illegal, YSRCP in a statement demanded that the Speaker explain constitutional validity of the 'merger'.
"Legislators have defected. That cannot be construed as the whole party has merged. The party is going to challenge the Speaker's decision," it said.