They have the numbers. Now, the two big regional parties — the Trinamool Congress and the AIADMK — want rooms in Parliament House that match their strength.
But it could be a tough call for the Lok Sabha Secretariat.
All the rooms on the much-sought-after ground floor — it has four big rooms — are occupied by the Bharatiya Janata Party (BJP), Congress, Telugu Desam Party (TDP) and the Janata Dal (United). The ground floor is always in demand for its easy accessibility and proximity to the chambers of ministers.
In the 2014 general elections, the AIADMK and the Trinamool have emerged as the third and fourth largest parties, respectively - after the BJP and the Congress.
While the AIADMK has 47 MPs (37 in Lok Sabha), the Trinamool has a total of 46 MPs (34 in Lok Sabha).
Tamil Nadu chief minister Jayalalithaa's AIADMK has a small room on the third floor of Parliament. Bengal chief minister Mamata Banerjee's Trinamool, however, does not have even that much of space.
"The Lok Sabha Secretariat will take care of this. But parties now in opposition should realise that their number has shrunk and those who have more MPs will need bigger rooms. They cannot just say that they will not vacate… since they have held a room for years," parliamentary affairs minister M Venkaiah Naidu said.
The secretariat is reportedly considering asking the JD(U), whose strength has been reduced to 11 MPs (just two in Lok Sabha), to vacate its office on the ground floor.
But, even if Bihar's ruling party vacates the room, that will not solve the problems of both the Trinamool and the AIADMK.
The ruling BJP, which has a total of 324 MPs (282 in Lok Sabha), and the Congress — with 111 MPs (44 in Lok Sabha) — will continue to hold the rooms allotted to them.
Also, convincing BJP ally TDP, Andhra Pradesh's ruling party, will not be easy. The party has 22 MPs — 16 of them in Lok Sabha.
"We have not received any communication. We have retained this office for years and we are not moving away," TDP's office secretary Satyanarayana said.
Trinamool Congress leaders Sudip Bandyopadhyay, Mukul Roy and Abhishek Banerjee had met Lok Sabha Speaker Sumitra Mahajan recently to get a room for an office in Parliament.
"We have been demanding a room since 2009. The strength of our party has increased since then. We need a space for them (the members)," Bandyopadhyay said.
A source told HT that AIADMK leaders had also taken up with competent authority the demand for a bigger room on the ground flood.
A senior official with Speaker Sumitra Mahajan's office said a decision on the subject was expected before the second half of the budget session in July.
"We will go by the rules and procedures," he said, preferring anonymity.
Amid the deadlock, parties such as the Rashtriya Janata Dal (RJD), which has a combined strength of five MPs (four in Lok Sabha), are not ready to concede.
The RJD holds a room on the third floor, and said it would protest if attempts were made to "snatch" the office space.
"We will not allow this to happen. We have held this office for years. We may be a smaller party now, but our size may grow next time," former minister and RJD parliamentarian JPN Yadav said.
Incidentally, the RJD office was allotted to the Trinamool in the United Progressive Alliance (UPA) government's term. But it did not budge.
Similarly, the TDP had foiled a bid by the UPA to allot its office to the DMK.
Meanwhile, the Bahujan Samaj Party (BSP), which drew a nil in the Lok Sabha polls, may manage to retain its office due to its strength in Rajya Sabha (14 MPs).
The DMK, which too could not win a seat in the Lok Sabha elections and has just four MPs, faces the risk of losing its office on the third floor of Parliament complex.