New Zealanders planning to work in Britain for six months or more will soon need an identification card containing their photograph, fingerprints and some personal details.

The compulsory Identity Cards for Foreign Nationals will have to be presented, with a passport, at the border from April next year to gain entry.

UK authorities say the cards, to be issued when any foreigner applies for a visa, contain the same details already recorded from passengers.

They expect the cards to make travelling, accessing medical services and setting up bank accounts quicker and easier.

Since Wednesday this week, sponsored skilled workers applying to extend their stay in the UK have needed to obtain a card.

By the end of this year, this will be widened to highly skilled and temporary workers who are extending their stay.

And by April next year, anyone working in Britain for six months or more will need a card.

British High Commission spokesman David Rose said yesterday that the system was introduced as part of a crackdown on illegal immigration and employment.

"These things are really designed to help legitimate migrants and legitimate employers. The only people who really have any need to worry are the illegal migrants or illegitimate employers."

Any employer or university found to be employing or educating a person without a card risked harsh penalties, including large fines and prison sentences, Mr Rose said.

"It will help those people make sure that anyone who comes to them has the legal right to work or study in the UK."

Mr Rose said two other types of cards were also being introduced.

British citizens would be required to get a National Identity Card.

Citizens of the European Economic Area and Switzerland working in Britain would also need their own identification cards.

Civil libertarians in the UK fear the cards will be an invasion of people's privacy.

But Mr Rose said there was nothing sinister about them. The microchip containing the fingerprint data was extremely secure.

He likened the microchips to New Zealand ePassports, which contain a facial biometric identifier of the holder.

"They can't be forged, they can't be tampered with," Mr Rose said.

The UK Border Agency first introduced biometric tests in November 2008.

"The purpose of this check is to verify that the individual entering the UK is the same person who applied for their visa, and using fingerprints enables us to do this with greater certainty," the agency's website says.

"By 2015, we expect that 90 per cent of nationals from outside the [European Economic Area] and Switzerland will have a card.

A Unisys Security Index survey released in October last year revealed that 81 per cent of New Zealanders were happy to use fingerprint scans to prove their identity.

Sixty-eight per cent were also willing to have their eyes scanned.