Britain's leading experts on tax and spending have warned George Osborne that weak tax receipts from the struggling economy have left him on course to miss his borrowing target by £13bn this year.

Adding to the pressure on the chancellor in advance of his autumn statement on 5 December, the Institute for Fiscal Studies (IFS) said government hopes of a small cut in the budget deficit would be dashed if the trend in the first seven months of 2012-13 continued for the rest of the year.

City analysts said news that borrowing in October was £2.7bn higher than in the same month of 2011 made it more likely that Osborne would fail to meet at least one of the two fiscal rules he announced when he became chancellor in May 2010.

But analysts said they expected the chancellor to push back the deadline for reducing Britain's debt as a proportion of national output by one or two years rather than risk stifling growth with fresh austerity measures.

Labour said data from the Office for National Statistics showing that borrowing in the first seven months of the 2012-13 financial year was £73.3bn – £5bn higher than in the same period of 2011-12 – illustrated the failure of the government's strategy.

Rachel Reeves, the shadow chief secretary to the Treasury, said: "George Osborne is borrowing billions more simply to pay for the cost of his economic failure. Having failed on jobs and growth, the government is now failing on the deficit too with government borrowing so far this year up by £5bn – a rise of 7.4%.

"With long-term unemployment rising and our economy flatlining, the welfare bill is now soaring while business tax receipts are down. By squeezing families and businesses too hard, choking off the recovery and so pushing borrowing up not down, the government's economic plan has completely backfired."

The Treasury said the latest figures showed that spending was under control, with most of the fall in tax receipts the result of production cutbacks in the North Sea. A spokesman said: "The economy is healing, but it still faces many challenges. These numbers illustrate that, but also show the government's plans to bring spending under control are on track for the year."

The autumn statement will be influenced by the judgments made by the independent Office for Budget Responsibility (OBR) on how the economy's future growth prospects will affect the public finances. Osborne has two fiscal rules – to start reducing debt as a share of GDP by 2015-16 and to ensure that by the end of a rolling five-year period the government balances its non-infrastructure budget after allowance for the state of the economy. The OBR said its forecasts at the time of the March budget implied a £1.5bn fall in government borrowing for the full financial year.

Rowena Crawford, a senior research economist at the IFS, said: "Today's figures will likely result in an unpleasant feeling of deja vu for the chancellor as he prepares for next month's autumn statement. As was the case last year, a worse-than-expected decline in corporation tax receipts in October has contributed to an overall picture of lower-than-expected growth in revenues so far this year. Spending on the administration and delivery of public services has also again grown more slowly so far than forecast for the year as a whole.

"Last year the level of underspending was sufficient to offset the lower-than-forecast growth in revenues at this point in the year, leaving borrowing looking broadly on course to meet the previous forecast. However, this year the potential spending undershoot looks to be able to offset only partially the weaker-than-expected receipts. If the trends in central government receipts and non-investment spending were to continue for the remainder of 2012-13, borrowing would come in £13bn higher than forecast by the Office for Budget Responsibility in March."

David Tinsley, UK economist at BNP Paribas, said: "In the short run the economy probably needs less austerity rather than more and the best approach in the autumn statement is for the chancellor to take the weakening in borrowing on the chin and emphasise that medium-term spending restraint appears to be working."