Shop price inflation has risen to the highest level in two and a half years, according to the British Retail Consortium, which warned that “the dam is starting to break” when it comes to retailers trying to limit price rises for customers.

The lobby group said shop price inflation was 2.1% year on year in October, a sharp rise compared with 1.4% in September, and an indication that retailers were beginning to pass on the rising costs of energy and food ingredients since the Middle East conflict broke out.