JAKARTA (AFP) - Indonesia has issued a decree allowing it to ban groups that oppose its official state ideology, in a move seen to target radical Islamists in the world's most populous Muslim-majority country.

The law, signed by President Joko Widodo on Monday (July 10), comes as concerns grow about the influence of hardliners in Indonesia, where a majority of the population practise a moderate form of Islam.

It empowers the government to disband without trial any group that challenges Pancasila, a set of founding national principles which promote pluralism and tolerance.

Pancasila is considered the unifying factor for a country home to significant Christian, Hindu and Buddhist minorities.

Security minister Wiranto, who goes by one name, said Wednesday the move was taken because some groups were "threatening the nation's existence and creating conflict in the society".

Neither Wiranto nor the decree name specific organisations.

But activists said the move is aimed to disband Hizb ut-Tahrir Indonesia (HTI), the local branch of a radical Islamist group that seeks to unify all Muslims into a caliphate.

The government said in May it wanted to take legal steps to dissolve the group.

"This decree is merely a shortcut to disband HTI because if they use the old NGO law, it's going to take a long time," legal expert Bivitri Susanti told AFP.

Mass organisations spreading ideologies such as atheism and communism are also banned under the decree.

Rights activists warned that the decree could stifle a broad range of democratic institutions.

"Banning any organization strictly on ideological grounds, including Pancasila, is a draconian action that undermines rights of freedom of association and expression," Andreas Harsono, a Human Rights Watch researcher in Jakarta, told AFP.

Asfinawati, the head of Indonesia Legal Aid Foundation, said the move is "a setback of Indonesia's democracy".

Wiranto denied that the decree aims to muffle NGOs.