I would something like: 
foreach my $line (@filedata) {
    s{(\Qhttp://v3vi.click4assistance.co.uk/c4a.aspx?AccNo=Inter12109&
+amp;IDENT=\E)US/${1}UK/g;
}

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In reply to Re: regex issue by JavaFan
in thread regex issue by rahulgsp83

Title:
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