Figures have been released which show the backlog of applications has increased, while at two passport offices processing delays have actually lengthened in the last week.

The Passport Agency admits the backlog is double what it was at the beginning of June and three times larger than it was a year ago.

The average waiting time for a passport at the Belfast and Glasgow offices has gone up to almost eight weeks, while improvements at London, Newport and Peterbrough offices have been slow, the agency says.

Staff working overtime

Only at the Liverpool office have things improved, with waiting times down from 10 weeks to seven.

The emergency extension of old passports to make them valid for another two years has only just begun to have an effect, say officials.

Staff are still working overtime to try to clear the mounting paperwork.

Computers which were initially blamed for the problems in Liverpool and Newport were due to be installed elsewhere this autumn, but this is likely to be postponed until the crisis has eased, says the BBC's Danny Shaw.