The Prime Minister's responding to flag referendum critics - he said the government can support social services and other issues at the same time.

The flag referendum, part two of which is to be held next month, drew criticism from stretched social services after it was announced it would cost $26 million dollars.

John Key said the government can - and does - focus on more than one thing at once:

"Of course the economy, law and order, health, education, poor children - of course those issues are more important. But as a country surely we can walk and chew gum at the same time. We can consider lots of different issues at once - we actually do."

Mr Key said the cost comes hand in hand with a democratic process such as a referendum.