The Election Act 2017, which paved the way for Nawaz Sharif to promptly be re-elected president of the ruling PML-N, was challenged in the Supreme Court on Tuesday.

A petition, filed under Article 184/3 of the Constitution, states that the bill "is against the basic spirit of the Constitution".

"A party leader controls voting in the National Assembly, as Article 63A of the Constitution states that an MNA can be disqualified if he or she votes against the official party line," the petition argues.

Until the bill stands as law "a disqualified person will continue to control the basic business of the National Assembly", which can be dangerous for the country, the petitioner, Advocate Zulfiqar Bhutta, has argued.

He has urged the SC to declare the bill null and void and without legal effect.

The government on Monday had bulldozed an amended Election Bill 2017 through the Lower House of parliament despite strong protests from opposition lawmakers.

The bill, subsequently signed into law, features a controversial amendment that will allow politicians disqualified from holding public office to head a political party.

Opposition lawmakers had protested loudly against the bill's passage, seeing it as a law designed to accommodate a single individual — ousted prime minister Nawaz Sharif.

Sharif was on Tuesday elected unopposed as PML-N president.