Lawyers for Pakistan's ousted ex-Prime Minister Nawaz Sharif have challenged his deportation in the Supreme Court.
Mr Sharif was deported back to Saudi Arabia on Monday, hours after landing in Islamabad to challenge the rule of President Pervez Musharraf.
Lawyers for Mr Sharif's PML(N) party say the move was illegal and amounted to contempt of court.
The Supreme Court has become a focus of opposition to Gen Musharraf after he tried to sack its top judge.
"We will fight this battle in the court of law," Mr Sharif's nephew, Hamza Sharif, said outside the court buildings in Islamabad, the Associated Press news agency reports.
"We are fully confident that we will win, God willing."
The petition seeks the return of Mr Sharif to Pakistan and asks for contempt charges to be brought against Prime Minister Shaukat Aziz, the Interior Minister, Aftab Sherpao, and various officials.
Mr Sharif originally went into exile in 2000 after being deposed by Gen Musharraf in a military coup a year earlier.
In August the Supreme Court said he was free to return.
His arrival in Islamabad on Monday - and dramatic deportation after being charged with money laundering and corruption - came as Gen Musharraf has faced mounting pressure to stand down.
Pakistan's deputy minister of information says Mr Sharif opted to leave Pakistan rather than be prosecuted for corruption, but the opposition says he was illegally expelled.
Pakistani troops surrounded his plane after it landed.
There was a stand-off on board as he refused to hand over his passport to immigration officials for nearly two hours.
Eventually he agreed to leave the plane and was escorted to the airport's VIP lounge.
But shortly afterwards he was separated from his entourage, charged with money laundering and corruption, and flown to Jeddah in Saudi Arabia.
Large numbers of police had set up barricades on roads to prevent Mr Sharif's supporters from reaching the airport on Monday.
Mr Sharif's supporters were kept away from the airport
There were reports of clashes between police and crowds of Mr Sharif's supporters in Islamabad, Rawalpindi, and Attok, where shots were fired and several people were said to have been injured.
One worker from Mr Sharif's faction of the Pakistan Muslim League party (PML-N) told the BBC that he and about 20 others had been badly beaten by police outside the airport.
Opposition activists have called for a day of demonstrations across Pakistan on Tuesday.
The BBC's Barbara Plett in Islamabad says it is not clear how much street power they will be able to muster. Many of their leaders are still in jail because of the security clampdown to thwart Mr Sharif's return from exile.
Another former Pakistani Prime Minister, Benazir Bhutto, has said Mr Sharif's deportation does not affect her own plans to return soon to Pakistan.
She is reported to be near a deal to share power with President Musharraf but nothing is finalised.