Tens of thousands of people are expected to take to the streets of Dublin on Saturday to protest against the government's harsh austerity plan.
The Irish Congress of Trade Unions has called the national demonstration to protest against a draconian austerity package designed to cut the country's massive deficit.
ICTU general secretary David Begg insisted the protest would be good-humoured and well organised after the police warned that some groups may be looking to exploit the event and cause trouble, the BBC reports.
The package will cut the minimum wage and slash 25,000 public sector jobs, as Ireland strives to bring its deficit back under 3% of gross domestic product by 2014 from its current level of 32%.
The march comes as the beleaguered Irish government was dealt a fresh blow with it's slim majority being cut further.
Sinn Fein, which campaigns for a united Ireland, has won its first by-election in the Republic for eighty-five years, taking the Donegal South-West seat from the governing Fianna Fail party, thereby reducing its majority to two.
The election was the first major poll in the country since the government sought a bail-out due to its fiscal deficit and concerns about its banks.
Mr Doherty won 13,719 first preference votes, 6,000 more than the Fianna Fail candidate.
He said the result had sent a message to Fianna Fail that its policies had been firmly rejected.
"Obviously we are absolutely blown over by the number of people who have come out and voted for Sinn Fein and our vision for this county and this country," he said.
Sinn Fein, who's leader is Gerry Adams, has a large presence in the Northern Ireland assembly where a senior member, Martin McGuinness, is the deputy First Minister. But in the Irish Republic their influence is more limited and they won just four seats in the 2007 election.
The seat became vacant after Pat Gallagher of Fianna Fail was elected to the European Parliament in 2009.
Fianna Fail's share of the vote fell from 50% in 2007 to just 21% in the by-election.
Mr Doherty is likely to be a member of the Irish parliament for only a short time with the Irish prime minister Brian Cowen promising a general election in the new year.
