Tax breaks to help working parents pay for childcare should be extended to workers assisting the disabled and elderly, employers have told the prime minister.

A letter to Gordon Brown and Alistair Darling, the chancellor - supported by BT, John Lewis. HBOS, IBM and KPMG - warns that a quarter of the population will be older than 65 within 30 years, requiring the number of carers to rise to 9m.