The UK's current account deficit, a key economic indicator, widened to a record level in the three months from July to September, official data shows.
Analysts say the government may borrow more than it forecast
The deficit was £20bn, or 5.7% of gross domestic product, compared with £13.7bn in the previous three months, the Office for National Statistics said.
Analysts also voiced concerns about the record level of government borrowing.
The data is evidence of a "dangerously unbalanced economy", according to Jonathan Loynes of Capital Economics.
In a monthly report on government financing, the Office for National Statistics said that public sector net borrowing hit a record £11.21bn in November.
Mr Loynes added that the borrowing figures suggested that the government was on track to overshoot its pre-Budget report forecast by at least £5bn this year.
"Overall, a pretty ugly picture, supporting our view that the coming economic slowdown will be a prolonged period of adjustment rather than a short pause for breath like that seen in 2005," he explained.
"What is really shocking about these figures is that they reveal that the Exchequer was running a large current deficit before the credit crisis hit home, when the economy was doing very well and it should have been showing a large current surplus," said Professor Peter Spencer, chief economic advisor to the Ernst & Young Item Club.