Aides to Pakistan's former Prime Minister Nawaz Sharif say the exiled leader is set to return to Pakistan before Monday's registration deadline for parliamentary elections.
Senior leaders of Mr. Sharif's Pakistan Muslim League Party say the former prime minister and members of his family will arrive in the eastern city of Lahore on Sunday.
Pakistani officials have not said if they will try to deport him, as they did when he attempted a similar return from exile in September.
Mr. Sharif's Pakistan Muslim League Party is a part of a coalition of opposition parties considering boycotting January's parliamentary elections.
Former cricket star and opposition leader Imran Khan told reporters on Saturday that participating in the poll would only give General Pervez Musharraf's presidency more legitimacy.
Mr. Sharif has been an outspoken critic of General Musharraf's imposition of emergency rule, urging Pakistanis to rise up against the president.
General Musharraf ousted Mr. Sharif in 1999 in a military coup.
Mr. Sharif was sentenced to life in prison, but General Musharraf allowed him to go into exile under a deal in which he promised to stay out of Pakistan for 10 years.
On Friday, Pakistan's Supreme Court ordered President Musharraf to step down as military chief and take the oath of office by December first. The court, stacked with judges appointed by General Musharraf, also declared that the November third imposition of a state of emergency and suspension of the constitution were legal.