National Insurance  

Experts say working pensioners should pay NI

He said: "When people have looked at things that interfere with work incentives, payroll social security taxes are generally perceived within the [Organisation for Economic Co-operation and Development] OECD as something which is a disincentive to participate in the labour market."

But Sir John said this was an empirical question, which he would like to see some evidence of.

He said: "We know the people who keep working past state pension age tend to be higher paid, they tend to have rewarding jobs, and I suspect the marginal effect would be small."