After laying off nearly half its staff over the last five years, scaling back street-cleaning and relying on volunteers to work at some of its libraries, the London borough of Lewisham is getting ready for what could be much more painful spending cuts.

Officials in Lewisham's town hall, like those across the country, know they will have to shoulder much of finance minister George Osborne's renewed push to fix Britain's budget.

Osborne is due to announce on Wednesday the details of a new spending squeeze which, according to International Monetary Fund data, ranks as the most aggressive austerity plan among the world's rich economies between now and 2020.

It is also a gamble by Osborne, a leading contender to be the next prime minister, that voters can stomach more cuts.

He rejects accusations that his insistence on a budget surplus by the end of the decade is a choice, saying Britain needs fiscal strength to fight off future shocks to the economy.

As in the first five years of his austerity push — which Osborne originally hoped would wipe out the budget deficit — he plans to spare Britain's health service, schools and foreign aid budget from his new cuts and will increase defence spending.

That means cuts for unprotected areas of government, such as local councils, will be deeper.

Kevin Bonavia, a councilor who oversees Lewisham's budget, said the borough had just agreed to merge computing teams with another one on the other side of London as it seeks to make more savings in its back-office operations and protect services.

But voters are likely to notice the cuts more in the years ahead than they have done so far. Rubbish bins may no longer be emptied weekly. Delivery of cooked meals could be replaced with help for people in need to do their own online shopping.

Lewisham will also have to find savings in the way it provides social care for the elderly and children, which accounts for the lion's share of its spending.

"We are always trying to rationalise. But we have to do it at pace now, and when you do it at pace, you can make mistakes," said Bonavia, a member of the opposition Labour Party.

It's not just Labour politicians who are worried about the latest spending squeeze.

The Conservative leader of a council in Oxfordshire recently wrote a blunt letter to Prime Minister David Cameron to spell out the challenge of funding care for the elderly and children after Cameron had complained about cuts to front-line services in the area, where he has a family home.

Britain's police departments and the justice system, which runs courts, are also likely to bear the brunt of further cuts.