Pakistan's Supreme Court on Tuesday reserved its verdict on a petition challenging the deputy speaker's ruling in the election of the Punjab chief minister which led to Hamza Shehbaz's victory.

PML-Q leader Chaudhry Parvez Elahi who lost the election held on Friday despite getting a majority vote challenged the ruling of deputy speaker Dost Mazari who handed victory to Hamza, son of Pakistan Prime Minister Shehbaz Sharif.

A three-member bench comprising Chief Justice Umar Ata Bandial, Justices Ijazul Ahsan and Munib Akhtar, which heard the case, is expected to announce the decision this evening.

The court went ahead with the proceedings despite the coalition government's decision to boycott the hearing after their petition seeking the formation of a full bench was turned down.

The Supreme Court on Monday refused to form a full bench to hear a case related to the re-election of Hamza as the Chief Minister of Punjab province, saying it will have to hear more arguments before taking a decision on the issue.

When the hearing began on Tuesday, the counsel for Mazari, Irfan Qadir, informed the court that his client had instructed him not to participate further in the case proceedings and he would instead file a petition for a review of the court's decision to not constitute a full bench.

Pakistan Peoples Party (PPP) counsel Farooq H Naek also declined to participate in the court hearing. However, they both stayed in the courtroom and watched the proceedings.

The case is about Mazari rejecting 10 votes of the Pakistan Muslim League-Quaid (PML-Q) in favor of Elahi by saying that the lawmakers violated the order from the party president Chaudhry Shujaat Hussain who asked them to vote for Hamza.

Elahi challenged the ruling by contending that Hussain was not authorised by law to issue such an order.