The Federal Court is set to rule on the controversy surrounding the construction of a minaret in a small town in northern Switzerland.
The dispute is one of several cases in the country, and comes as some rightwing groups are attempting to fuel the debate over minarets.
Opponents of the minaret in Wangen near Olten said they would hand in their appeal before the deadline runs out at the beginning of January.
A lawyer said it was not yet clear whether the group would also ask the court to delay the beginning of construction work while the case is pending in court.
The opponents argue they are not willing to tolerate neighbours who allegedly belong to an extremist organisation.
There were reports that the Turkish organisation which wants to build the minaret in Wangen had links to the extremist Grey Wolves, the youth organisation of the Turkish Nationalist Movement Party.
Last month a cantonal court decided to throw out a legal complaint, saying the planned minaret was not in breach of regulations unless it had loudspeakers for calling worshippers to prayer.
Moves to block the construction of minarets are also underway in other regions of the country.
The cantonal parliaments of Zurich, Bern, St Gallen and Ticino are considering proposals to make the construction of buildings of worship, such as minarets, temples and churches, dependent on approval at the ballot box.
On a local level, rightwing extremists in the town of Langenthal in canton Bern have collected signatures and organised public protests against mosques.
Furthermore, a committee that includes parliamentarians from the rightwing Swiss People's Party has announced an initiative aimed at blocking the construction of minarets.
The campaign to collect the necessary signatures for a nationwide vote on the issue is planned for spring 2007.
Currently only two mosques in Zurich and Geneva have a minaret. There are about 340,000 Muslims in Switzerland, mainly from the Balkans and Turkey, representing up to five per cent of the Swiss population.
swissinfo with agencies
Building plans for minarets have been submitted in several places, including Wangen near Olten, Langenthal in canton Bern and Wil in canton St Gallen.
A recent report from the Swiss Federal Commission Against Racism called for more tolerance towards Muslims and highlighted the minaret controversy in Wangen.
A minaret is a tower, traditionally part of a mosque, with a balcony from which a muezzin calls Muslims to prayer. In modern mosques, the minaret is equipped with loudspeakers.
In Switzerland, only the mosques in Geneva and Zurich have a minaret. The call to prayer is not made from these minarets.
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