The supporters, who were gathering for a party congress, waved Islamic party flags dating from before 1987, when the government banned them in favour of a more secular representation.

Estimates of the size of the rally ranged from 50,000 to 100,000.

There were no reports of violence, in contrast to recent widespead unrest around Indonesia.

PPP chairman Ismail Hasan Metareum, called on President BJ Habibie to keep his promise to hold elections in June.

"If Habibie is able to create a democratic foundation for the government and organise a democratic general election, his short government will be remembered and respected," Mr Metareum said.

"The next general election should be free from filthy practices."

Islamic emblem restored

The PPP leader said that an image of the Kaaba, Islam's holiest shrine, would be adopted once again as a party emblem during the congress. In 1982 the party was forced by the government to adopt a more secular emblem in the form of a star.

"Secularists are afraid to see the United Development Party become big ... because this party is able to promote itself as the defender and guardian of Muslim teachings," Mr Metareum said.

The five-day congress is expected to choose a new leader to take the party into the promised elections.