The TUC is organising the protest in London on March 26 and said that by then, the impact of the austerity measures would have started to take hold, with an expected loss of tens of thousands of jobs.
Union members from across the UK are set to join the demonstration in Hyde Park, which will follow a series of protests in recent weeks against increases in student tuition fees and cuts in public services.
TUC general secretary Brendan Barber said: "People have yet to feel the full impact of the Government's cuts. When they do – as we saw with the cancellation of the schools building programme – they have been angry."
He said thousands of people would lose their job in 2011. "As it becomes more and more obvious that the cuts bear down on those who did least to cause the crash, while those who were responsible continue to live in their bonus-driven super-rich bubble, people will get even angrier." Mr Barber said the "March for the Alternative" would be a huge event, adding there will also be thousands of local campaigns.
"As well as traditional campaign events, the new power of the internet makes it easy for people to come together quickly as we have see in the imaginative protests against tax avoidance in high streets throughout the country."
"The British people may not be easily roused, but we do have a deep sense of national fairness that goes across traditional party loyalties. As the cuts, that many economists say are too deep and too drastic, start to bite, unemployment rises and low and middle income earners find they are bearing the brunt, the Government could well find that it needs to change course or it could find the country united against it."