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Personal savings will be the primary source of retirement income, followed by a company retirement plan, with 35 and 29 percent of Britons citing these sources respectively.
One in four say a state pension will be their main source of retirement income, which is half the European average of 49 percent.
"Britons have a bleaker retirement outlook than people globally; they're almost twice as likely to expect to be working after 65, and a third less likely to believe they'll be financially better off than their parents," said Nielsen senior vice-president for financial services in Europe, Eleni Nicholas.
The poll surveyed 30,000 internet respondents in 60 countries, and revealed that 46 percent of British workers said they will retire later then they would like.
The findings come as CEO of the world's largest asset manager has suggested that saving for retirement in the U.K. should be compulsory and would help solve the pensions "crisis".
(Read more: Retirement funds and ramen noodles: Saving smarter in your 20s)
Speaking at the National Association of Pension Funds (NAPF) investments conference in Edinburgh last week, BlackRock's Larry Fink said there should be no opportunity for workers saving for retirement to "opt-out".
"As I have advocated in the U.S., I would recommend simply making an appropriate level of retirement savings mandatory here in the UK, without the opportunity to opt-out," said Fink.
"This has been done with the superannuation system in Australia and has proven to be extremely effective. There is too much risk that people will either opt out, or not put enough away even if they remain in a plan," he said.
Fink also presented new BlackRock analysis of the UK annuities market suggesting the cost of retirement income has doubled over the last 40 years.
One in two U.K. adults have yet to start saving for retirement, according to BlackRock's Investor Pulse Survey and research by the Policy Exchange also shows the average U.K. worker has a pension pot of just £36,800, ($61,599) which will likely yield an income of only £1,340 a year in retirement.
(Read more: Is Gen X ready to retire? Depends who you ask)
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