More than 100,000 jobs could go across the South East due to public sector cuts, according to a new report.
A South East England Development Agency (Seeda) survey predicts the jobs will be lost by the end of March 2016.
The report said Hastings in Sussex and Canterbury in Kent, which were most reliant on the public sector, could be worst hit by the Spending Review cuts.
Seeda, which is due to be abolished in 2012, has refused to comment on the figures in its document.
The report states: "Based on the OBR [Office for Budget Responsibility] forecast, it is estimated that we could see 74,000 public sector job losses in the South East between now and the end of the 2015/16 financial year.
"This translates to slightly under 2% of the workforce losing their jobs, rising to around 3% in the most affected areas."
It continues: "We are likely to see a number of private sector job losses as an indirect effect of public sector cuts. This could push total job losses in the South East above 100,000."
The public sector employs about 630,000 people, 15% of the workforce, in Kent, Sussex, Surrey, Hampshire, the Isle of Wight, Berkshire and Oxfordshire.
Zoe Van Dijk, regional officer for Unison, said: "The effect on the local economy will be devastating because if people are working they spend money.
"Where local authority jobs are lost there is a knock on effect, other firms who rely on trade from these workers will suffer."
She added: "It affects confidence. Those still in work won't spend money through fear they will be losing their jobs.
"The idea that debt will be recovered over five years will be nonsense - it took 60 years to pay for the war. We haven't suffered from that."
Jo James, chief executive of Kent Invicta Chamber of Commerce, said potential job losses could be limited if businesses in the South East were prepared to be more creative.
She added: "From a private sector perspective it is going to open up opportunities.
"There's been somebody providing these services and if it is a service that is going to continue than it can be outsourced. Businesses have to be ready for that.
"In a place like Canterbury there are 60,000 employees in the Canterbury district, 42% of these being employed in the public sector, and large proportion of those being in FE [further education] and HE [higher education].
"I'm not saying they are going to be sheltered but I think it is going to effect local based central government departments more."
Ms James said: "All local authorities are going to do everything they can to mitigate the losses. Although we are losing it from one area we are gaining it in another area."
The UK government's comprehensive spending review on 20 October will announce cuts aimed at tackling the country's deficit.