Underlying inflation is forecast to have climbed by 0.3 per cent to 1.8 per cent in July, but most of the rise will be due to one-off "base" effects.
Falls in the price of seasonal food and petrol have been far less than a year ago, thereby fuelling an increase in the annual inflation measure.
Underlying inflation dropped to its lowest level on record in June, 1.5 per cent, the extreme lower end of the Chancellor's target range for the Bank.
The Bank of England said in last week's quarterly inflation report that the underlying rate would rise above 2 per cent by the end of the year.
Philip Shaw, chief economist at Investec, said he believed the Bank was likely to be "far from comfortable" with inflation in such a benign state.
A rise in the underlying rate, which excludes mortgage interest payments, to 1.8 per cent would still leave it at its joint lowest ever level, excluding June.
Mr Shaw said that on balance Investec felt a reduction in interest rates to 3.75 per cent was likely in the fourth quarter of this year.
The US Federal Reserve meets to set interest rates in America today and opinion is mixed about whether it will lower the cost of borrowing.
There was growing speculation last week the Fed may cut from the current 1.75 per cent to protect the US economy from falling into a "double-dip" recession.
