The public interest litigation (PIL), filed by advocates Manmohan Singh and Shishmita Kumari, may be heard by a vacation Bench on June 26.
They have also sought direction to the Speaker to frame a policy for the leader of opposition's appointment.
"In the new Lok Sabha, with 52 members, the Congress is the largest party in the opposition and is, therefore, the rightful claimant to the post under the law. There is no ambiguity about it as the law is absolutely clear on this point," they stated.
Denying the second largest party in Parliament (Lok Sabha) the leadership of the opposition would set the wrong precedent and dilute democracy, they said. A powerful opposition was necessary to check the ruling party as dissent was extremely important for democracies to function properly, they added.
They said that the Congress could not claim the leader of opposition's post because it did not have 10 per cent of the total MPs in the House was devoid of any merit.
The petitioners told the court recognising a member of the House as the leader of opposition was not a political or arithmetical decision, but a statutory decision. The Speaker has to merely ascertain whether the party claiming the post was the largest party in the opposition.
"That the leader of opposition is one of the key parliamentary functionaries whose role, though not defined in any rule, is of great importance for the functioning of a legislature. He or she is invariably a senior leader, representing the main opposition party in the legislature," the plea read.
Since the post was statutory, one needed to only look into the law to find out who could become the leader of opposition and how he or she was to be recognised, the plea read.
"There is no room for ifs and buts, under the Salaries and Allowances of Leaders of Opposition in Parliament Act, 1977, the duty of the Speaker is to recognise the eligible person as the leader of opposition," they stated
They also argued since the Speaker was performing a statutory duty in recognising the leader of opposition, she or he could not exercise any discretion.
( With inputs from IANS )