Compulsory powers to fingerprint and photograph 700,000 foreigners a year who live in Britain as part of the national identity card scheme were announced yesterday by the home secretary, John Reid, as the scope of what critics see as a future Big Brother state became clearer.

At the same time, 150 screening centres around the world are to be set up in 18 months so that biometric data - electronic fingerprints and photos - can be taken and stored from passengers coming to Britain from 169 countries outside Europe.

But Mr Reid had to confirm that the Home Office's original plans for one huge new "clean" database to store the details of everyone resident in Britain have had to be scaled back on the grounds of expense as the government tries to cut the estimated £5.4bn cost of introducing ID cards. The controversial national identity register, which will store everyone's biometric fingerprints and photographs as well as personal biographical details, will now be housed on three separate existing government computer systems.

Mr Reid denied yesterday that this was a U-turn, although the computer industry has widely seen the decision as a significant change of tack: "Doing something sensible is not necessarily a U-turn," said Mr Reid. "We have decided it is lower-risk, more efficient and faster to take the infrastructure that already exists, although the data will be drawn from other sources."

An "action plan" produced by the Home Office yesterday said that existing Department for Work and Pensions technology used for national insurance records would store biographical parts of a person's national identity register entry. Home Office systems used to hold data on asylum seekers will be expanded to hold the biometric photographs and fingerprints.

Private companies will be invited to bid for contracts to develop these databases in the next six months.

The Home Office claimed that the split between different databases would guard against malicious or fraudulent damage. Mr Reid said that it would also reduce the overall £5.4bn cost of the ID project but declined to give a new estimate, saying it would be reported to parliament next April.

He also confirmed that the current price excludes issuing the compulsory resident permits to foreign nationals living in Britain. Increased fees and charges for renewing their visas are expected to cover the extra cost. While ID cards are unlikely to be compulsory for British residents before 2011, foreign nationals will have to give their fingerprints for a compulsory foreigners' ID card from 2008.

Biometric checks on non-European travellers to Britain from 2008 would in volve a "triple check" before they stepped on to the plane, said the immigration minister, Liam Byrne.

Everyone from the 169 countries outside the European Economic Area who intends to work, study or stay in Britain for more than six months will be expected from 2008 to provide their fingerprints and photograph before they travel.

The biometric details of visitors from 108 countries of the 169 that have a visa agreement with Britain will also have to be provided, even if they are coming to the UK just for one day. Already 450,000 people have been refused entry to Britain last year for failing this pre-departure test.

Mr Reid said this extension abroad of the national identity scheme would mean that "people we are concerned about will be stopped from coming here before they travel" and it would make illegal working in Britain much more difficult. But critics claim that Mr Reid is building a "database state" in which ministers are trying to use computers to manage people by watching them. The director of human rights group Liberty, Shami Chakrabarti, said: "Nothing short of repeal of this act will do."

The timetable

2007 Biometric visas issued at 150 posts abroad; new passport readers at key airports; tenders invited for first phase of ID databases.

2008 Fingerprints and photos taken of all foreign nationals applying for visas: compulsory biometric ID cards for foreign nationals living, working or studying in the UK.

2009 Fingerprinting for ID cards starts and first Icards issued to British citizens; electronic background checks on 120m passengers (60%) before they travel to Britain; UK employers start online identity checks of foreign staff.

2010 Electronic background checks on 190 million travellers (95%) coming to Britain.

2011? Parliament votes on making ID cards compulsory for all British residents plus all foreign nationals living in Britain.