Surakarta – Unregistered marriages must be stopped because they cause problems for both parties, radical cleric Abu Bakar Ba'asyir said recently to Antara.

"It's best if this practice is banned outright," Ba'asyir, of the Pondok Pesantren Al Mukmin (Islamic boarding school) in Central Java, said Monday.

"Nikah siri, or marriages not officially registered with the KUA, were recently deemed legal under religious law, but this can cause undue harm."

According to Ba'asyir, unofficial marriages are opted for because those involved want to keep their marriage a secret, a contradiction to the idea of marriage being a celebration known to all.

"One who doesn't want their marriage known is a coward. The state needs to immediately take action and stop this kind of arrangement," he said.

"If a man wants to practice polygamy, then he should have good intentions and treat his wives in a just manner," he added. If he is unable to do so, then he should not take more than one wife, Ba'asyir added.

Unregistered marriages are widespread in Indonesia's predominantly Muslim population because they are recognized by Islam. A recent survey found polygamy was a significant factor behind the country's rising divorce rate.