A plea filed by the party stated that Mohsin Naqvi was 'biased' and his appointment as Punjab caretaker chief minister would affect transparency of elections.
PTI has also challenged the appointment of Raja Riaz as opposition leader.
Earlier, former CM Chaudhry Parvez Elahi also questioned how one could expect justice from a person who had struck a plea bargain in the Haris Steel case.
“How can my close relative become the caretaker chief minister?” he questioned, terming the ECP’s “controversial” decision to be in violation of the rules. “We will approach the Supreme Court against ECP’s decision.”