To mark the occasion, Spain's Equality Minister Ana Redondo announced on Friday the government would revive a human trafficking law which was proposed last year but was not passed because of July's general election.

The new legislation will mean that, among other things, victims will not be obliged to make an official report which can sometimes deter them from making claims about alleged traffickers.

In Madrid, the Plaza Cibeles fountain was turned purple with lights to mark the colour of the feminist movement while protesters wearing white masks and disguises took to the streets.

"We women, we haven't been heard for a long time and we are so tired of not having the same benefits and having to struggle to the basic needs," Natalia Hofmann, 34, a psychologist, said in an interview in Barcelona.

Protests were held by thousands of feminist groups in 40 Spanish cities.

(Reporting by Graham Keeley, Guillermo Martinez, Marco Trujillo, Miguel Gutierrez, Horaci Garcia and Catherine Macdonald; editing by Jonathan Oatis)