Several thousand people have taken part in a march through Belfast city centre in protest at austerity measures being introduced by governments in Dublin and London.
The rally was organised by the Northern Ireland committee of the Irish Congress of Trade Unions.
Many of the associated organisations paraded through Belfast behind their union banners.
SIPTU president Jack O'Connor said the message was that working people in Europe would ultimately resist austerity measures when it becomes clear the policies are not working.
ICTU Assistant General Secretary Peter Bunting told workers they had too often been divided into sectarian blocs.
"We cannot allow that to happen ever again," he said.
"We shall resist such cynical, sectarian manipulation and we shall unite to resist the unworkable and cruel cult of austerity."
Earlier this month MLAs voted in favour of introducing controversial welfare system reforms similar to those enacted in England and Wales.
Mr Bunting added: "Let us work with our comrades and colleagues in Wales, Scotland and England to build an arc of resistance that rejects the economic diktats of the Conservative minority.
"The devolved administrations must build a robust joint defence of the people who elected them.
"Let this rally today send a message to our MLAs and our MPs from all political parties that we the people are firmly opposed to the failed policy of austerity which destroys lives and futures.
"We demand that they stand up for the people of Northern Ireland and refuse to slavishly implement the cuts."
Similar demonstrations also took place in London and Glasgow.