The law is that there must always be an excess of children in order that there may be enough cheap workers.

The phrase means bringing in cheap workers from other countries who undercut local workers, and who can even deprive locals of jobs.

Although some companies undoubtedly use the program to import cheap workers and keep wages low, others rely on it to attract much-needed skills.

Carl McLennan, also a superintendent in the New Zealand police, says smugglers use drug dependent Pacific people as cheap workers in their illicit enterprises.

It was a "ploy", he said, to import tens of thousands of cheap workers and thus allow German employers to bring down wages.

French anxieties about cheap workers or German worries about integrating refugees do not exactly reflect the British rejection of migration, but there are common threads.