Britain's top police officer has backed calls for the quick introduction of ID cards and criticised a senior minister for saying it will take "many years".
Sir John has come out firmly in favour of ID cards
Met Commissioner Sir John Stevens said Patricia Hewitt was "wrong" and that ID cards were needed as soon as possible.
He said new technology had made him change his mind on the issue.
He agreed some of Britain's borders were porous and told GMTV: "This is why I think identification cards would be of great assistance."
On Thursday Prime Minister Tony Blair said identity cards would be introduced "more quickly than even we anticipated".
He told his monthly news conference the government had won over those who opposed the controversial measure for civil liberties reasons.
Practical issues and logistics were the only things stopping the introduction of ID cards, he told reporters.
In his interview Sir John said: "Up to a year and a half ago I would have been against identification cards because we had no certainty that the documentation used for identification cards could actually prove with certainty the identification of someone.
"Biometrics, the use of eyes, the use of fingerprints is now a certainty in a way that never was before so therefore identification either whether it be on border controls or whether we have to deal with stop and search in the street, anti-terrorism kind of activity or even along the normal way that police officers work would give a certainty we need."
On Ms Hewitt's remarks about ID cards he said he "disagreed totally" with the trade secretary, adding that the sooner the legislation was passed the better.
Sir John was also asked about his assertion at a joint news conference with London Mayor Ken Livingstone last month that a terror attack on London was "inevitable".
His remark was slapped down at the time by Home Secretary David Blunkett.
Blair says ministers have won over civil liberties concerns
Sir John pointed out that he had also attempted at the time to reassure the public the necessary steps were being taken to tackle terrorism.
He said: "We have the most highly efficient counter-terrorist effort that's ever taken place in the world over 32 years of Irish terrorism and further we have preventative measures."
Sir John added it was important to balance telling the public enough but not letting terrorists hamper people's normal daily activities.
Mr Blair's comments on identity cards came just two days after police arrested eight British men thought to be of Pakistani descent in raids across south-east England over an alleged bomb plot.
During his Downing Street briefing to press, Mr Blair indicated that he was now prepared to draw up further anti-terrorist legislation because of the new world situation.
"We need to make sure that in the light of fresh information and operations such as the one we have just seen that we are keeping our law up to date with the reality on the ground," he said.
"I think that the whole issue of identity cards, which a few years ago were not on anyone's agenda, are very much on the political agenda here - probably more quickly even than we anticipated."