Malaysia's Islamic opposition leader, Fadzil Noor, is in critical condition in the capital, Kuala Lumpur, following heart surgery this week. His illness could set the stage for a change of leadership in the Pan-Malaysian Islamic Party, or PAS.

PAS President Fadzil Noor is still unconscious, five days after the heart surgery. An aide says Mr. Fadzil is in the intensive care unit and his condition is stable. The aide says the party has not moved to replace Mr. Fadzil.

His illness, however, comes amid speculation that hardline party members want to replace the 65-year-old Mr. Fadzil, to prepare for the possibility of a general election next year. Some political analysts say Mr. Fadzil's ill health has been weakening his position in the party for some time.

Abdul Hadi Awang, the chief minister of the state of Terengganu, is standing in for Mr. Fadzil. Mr. Abdul Hadi is one of Mr. Fadzil's closet party allies.

PAS aims to turn multi-ethnic Malaysia into an Islamic state, although only a little over half of the 23 million citizens are Muslims. The country now has a secular government and its current leader, Prime Minister Mahathir Mohamad, has pledged to maintain it.

The Islamic party holds 27 of Malaysia's 193 federal parliament seats and controls the assemblies in two of its 13 states. PAS is the strongest opposition party in Malaysia and its support in some states has grown in the past few years.

Ho Khai Leong is a political scientist at the National University of Singapore. He expects no significant changes in PAS if Mr. Fadzil does not return to his post and Abdul Hadi Awang becomes party president. Dr. Ho says that Mr. Fadzil and Mr. Abdul Hadi "are radicals". He also says that if Mr. Abdul Hadi takes over the presidency, he will continue "what PAS has advocated all along."

While there may be a power struggle among factions within PAS to align themselves with the new leadership, Dr. Ho does not expect this to weaken the party's political objectives.