David Cameron, prime minister, calls on unions to accept that changes to public service pensions are both necessary and fair:

"I know why people care so much about this issue. The provision of good, high quality public service pensions goes to the heart of the kind of society we are. It's a vital part of the contract between all those who work in our schools and hospitals, fire stations and police stations, councils and prisons and the rest of the country.

"It's about saying: you've spent your career serving others; so we will look after you in old age. And I am determined to not just meet that contract, but to strengthen it.

"But here's the truth. That won't happen if we delay action, or even worse refuse to act.

"All that will mean is a worse pension system in five, ten, fifteen years time as the obligations become unaffordable. The fact is we will only meet and strengthen that contract through change.

"And the changes we propose are a good deal. They are fair for the lower paid and fair on the taxpayer. They secure affordable pensions not just now, but for decades to come.

"And they mean public service pensions will remain among the very best available. So to those considering strike action, at a time when discussions are ongoing, I would say to you: these strikes are wrong – for you, for the people you serve, for the good of the country. It's the changes we propose that are right.

"Right for the long-term. Right by the taxpayer. And most crucially of all, right by you."