Pakistan's electoral commission on October 21 disqualified former Prime Minister Imran Khan from running for public office for five years on charges of unlawfully selling gifts received from heads of state during his term in power.
Khan was also accused of concealing the money he obtained from selling some of the gifts in violation of the obligation of elected officials to declare all their assets.
Pakistani government officials are allowed to keep gifts below a certain value.
"The ECP (Election Commission of Pakistan) has declared Imran Khan was involved in corrupt practices," said lawyer Gohar Khan, adding, "We are going to challenge (the decision) in the Islamabad high court right now."
The ECP also ordered the initiation of a criminal case against Khan.
Khan's Tehrik-e Insaf (PTI) party urged supporters to take to the streets to peacefully condemn the commission’s decision.
"We don't accept this decision. The people of Pakistan won't accept this," Khan's spokesman, Fawad Chaudhry, told reporters. "I urge people to come out and throw out the rulers."
Legal experts say Khan, who was prime minister from 2018 until being ousted in a no-confidence vote in parliament in April, will lose his seat in the National Assembly under the ECP verdict.
Since his ouster, Khan, who is 70, has claimed his government was toppled by Prime Minister Shabaz Sharif's government as part of a U.S. plot.
Sharif and Washington both have denied the allegation.
This week, Khan's PTI won six of eight national assembly seats it stood for in a weekend by-election, a vote the former cricket star called a referendum on his popularity.