ISLAMABAD — A Supreme Court stacked with judges loyal to President Musharraf cleared the way Thursday for him to rule as a civilian president, throwing out a final challenge to last month’s election.

The decision, which was widely expected after General Musharraf purged the court of independent-minded judges, means that Pakistan’s Election Commission can put a stamp of approval on the October vote that won General Musharraf a five-year-term.

The general has said that once he got a court decision in his favor, he would quickly step down as army chief and take the oath as president. Attorney General Malik Mohammed Qayyum has said such a move could come as early as Saturday.

The court decision “means there is no challenge to his eligibility (to serve as president) and to the election,” Mr. Qayyum told reporters. He said the court would issue a directive to election authorities on Friday ordering them to ratify the result.

After that, he said, “the president will be free to take the oath” as a civilian president.

Immediate reaction from General Musharraf’s opposition was muted.

A spokeswoman for opposition leader Benazir Bhutto, Sherry Rehman, said she had no immediate comment.

An official with a powerful religious coalition, the Muttahida Majlis-e-Amal, said the ruling was “not unexpected,” adding that the important thing is for General Musharraf to make good on his promise to quit as army chief as soon as possible.

A decision by Ms. Bhutto’s Pakistan People’s Party and other opposition groups on whether to participate in parliamentary elections slated for January 8 is seen as a critical test for whether General Musharraf can weather the political storm around him. Analysts say that if they boycott the vote, as they have threatened, it will be difficult for him to claim any legitimacy.

The case before the court on Thursday centered on a claim by a would-be rival candidate, Zahoor Mehdi, who was blocked by the Election Commission from competing in the vote. He argued the decision was wrong, but the court said his nomination papers were not valid. Five other cases challenging the presidential election were either thrown out or withdrawn on Monday.

It is still not clear whether General Musharraf will lift the state of emergency, despite international pressure, including from America, his key backer. The Supreme Court was also considering challenges to emergency rule, and a decision was expected by Friday.

Late Wednesday, General Musharraf decreed new amendments to the constitution using powers he said he has under the emergency. One of the amendments states that his decisions cannot be challenged by any court and will be considered “always to have been validly made.”

Also Wednesday, the government freed more jailed political activists, including two of General Musharraf’s key opponents.

Law Minister Afzal Hayder announced on state television that the government had released 5,634 lawyers and political party members. He said 623 people remained in custody, but that they would be let go soon.