A group of female activists from the Beoung Kak lake community, where hundreds of poor families have been evicted to make way for a real-estate development, were prevented from marching to City Hall.
''There are over 100 riot police blocking the road and about 200 (activists)- mainly women and monks,'' said Moses Ngeth, of local labour NGO The Community Legal Education Centre.
''They want to submit a petition to end violence against women to City Hall,'' Ngeth said, adding that while there was no violence the women had been told they could not march. A forum planned by union representatives in a park in the capital was unable to go ahead because the area was blocked off with barricades and riot police as well as trucks with teargas.
Asked why women, monks, and union representatives had been prevented from gathering Saturday, Phay Siphan, spokesman for the Council of Ministers, said it was to prevent a ``messy'' situation.
''They challenge the government. They are troublemakers,'' he said of the Women's Day marchers, while insisting the government supported the message of ending violence against women. ''They don't need to take to a public place - the street.''
He also said unions should go back to the negotiating table with the government instead of holding a public rally.
''A special committee is working on the minimum wage (issue),'' he added.
Unions had called the event to discuss wage negotiations ahead of a mass stay-away by garment workers scheduled to begin Wednesday.
The unions want the minimum wage for the workers in the garment industry to be raised from US$100 (3,200 baht) to $160 a month.
Clothing is Cambodia's biggest export industry, and factories in the country produce clothes for high-street brands such as Gap and H&M.