David Lloyd-George was Chancellor when he introduced the first general old-age pensions.

People did not have to contribute money towards the payments, but they were means-tested.

From 1909, pensions of between two shillings (10p) and five shillings (25p) a week were available only to people aged over 70.

The amount was raised to 10 shillings (50p) in 1925, when 65 became the key pension age and benefits for widows began.

Worries about the costs of pensions are nothing new.

In the 1940s, Chancellor of the Exchequer Sir John Anderson warned that the "burden of the old" on workers would approximately double during the next 30 years.

That problem of an ageing population is the focus of a government-commissioned report which is due to be published this autumn.

The pre-First World War Liberal governments also marked the beginnings of national insurance.

"National health insurance" and more limited unemployment insurance were introduced for manual workers and non-manual workers earning less than £160 a year.

But it only really covered treatment from GPs - not from specialists.