It may cost as much as £10.7bn ($15.8bn) to replace IT infrastructure destroyed last week in terrorist attacks on New York and Washington.
California-based research firm Computer Economics puts the immediate cost of replacing equipment and keeping services operational, employing 25,000 IT and telecoms workers plus contractors, at £1.2bn ($1.7bn).
Long term, the firm estimates that some 100,000 information-intensive staff will have to be relocated to new facilities, requiring the installation of telecoms and datacoms support plus replacement servers, computers and workstations at a cost of £5.5bn ($8.1bn).
A further £4bn ($6bn) may be needed to replace the telecoms infrastructure itself once the extent of the damage to Manhattan has been determined.
A note from Computer Economics states: "It may take several weeks to determine the full extent of damage to communications facilities in Manhattan. It is clear, however, that many facilities have been rendered inoperative.
"It has taken many years to build up the infrastructure. In addition, the underground installations of Manhattan have, and will continue to be, damaged as the clean up and reconstruction takes place over the next several years."
Insurers and credit agencies have said that their total liabilities could reach as much as £20bn ($30bn).
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