Congress MLAs from Nellore district Sridhara Krishna Reddy and A Prabhakar Reddy said they are resigning in support of the demand for keeping Andhra Pradesh united.
The development comes amid assertion by the Congress' central leadership that consultation process over Telangana is over and time for a decision has come.
A ruling party MLA and 16 YSR Congress legislators from non-Telangana regions yesterday said they have "resigned" in support of a united Andhra Pradesh.
Except YSR Congress' floor leader in Assembly Y S Vijayamma, all the other 16 MLAs had "quit" their posts "individually", party sources said.
Alleging that Congress is more concerned about its political future in deciding the Telangana issue, YSRCP MLAs said it should first spell out its stance over the matter and consult all parties before taking any decision.
Congress MLA from Kamalapuram in Kadapa district G Veerasiva Reddy also said he has resigned from his post and also from the party.
Dismissing the resignations by YSRCP MLAs as political opportunism, APCC chief Botsa Satyanarayana said the Jaganmohan Reddy-led party should first announce its own stance on the Telangana issue.
The resignations were expected to put pressure on the legislators from Rayalaseema and coastal Andhra to quit in the event of the Centre taking a favourable decision on Telangana.
Competitive resignations have become routine in Andhra Pradesh ever since the contentious Telangana issue took the centre-stage in 2009.