Due to strict work permit levies. Teacher supply agencies are being forced to search as far afield as Canada and Singapore to plug school staffing gaps as a result of a shortage of fully trained recruits in the UK, according to a report by The Independent. However, strict limits on work permits have meant that up to 60 teachers recruited from the USA to start work in September are unlikely to turn up – as they have been refused permission to work in the UK.

Source: British recruiters to raid Singapore schools for teachers | Singapore Business Review