Cabinet has decided that New Zealand will have a one-off public holiday and state memorial service to mark the death of Queen Elizabeth II.

The one-off holiday will be held on Monday 26 September.

In a statement, Prime Minister Jacinda Ardern said many New Zealanders would appreciate the opportunity to both mark her death and celebrate her life.

"The State Memorial Service will be held in the Wellington Cathedral of St Paul on the same day, Monday 26 September, and will be televised and live streamed.

"I know many people will want the opportunity to pay their respects and the public holiday offers communities around the country the ability to come together and pay tribute at local events also."

It was appropriate to mark the life of New Zealand's much loved Sovereign with a dedicated public holiday and State Memorial Service, Ardern said.

It was in keeping with an historic event and in line with the UK and Australia, which were having similar holidays, she said.

Ardern also confirmed she would represent New Zealand, alongside the governor-general, at the funeral of Queen Elizabeth II in London. Ardern will depart New Zealand on Wednesday 14 September.

The Queen died on Friday (NZT) and will lie in state for four days before her funeral at Westminster Abbey on Monday, 19 September, which will be a public holiday in Britain, officials announced.

BusinessNZ this morning said it did not support a public holiday to honour the late Queen Elizabeth II because it would be costly for businesses which had already suffered losses from the pandemic.

Australia has already confirmed its one-off public holiday for the National Day of Mourning on 22 September.

Condolence books are available around the country for people who want to pay tribute following the death of Queen Elizabeth II.

The official proclamation of Charles III as Aotearoa New Zealand's new king has took place at Parliament yesterday.