Thanks pixie. We'll I'm puzzled then because that doesn't match my understanding of zero hours contracts.
This ACAS site for example says employees are NOT obliged to accept work:
http://www.acas.org.uk/index.aspx?articleid=3886
“Generally, as an employer, you are not obliged to offer work to workers on zero-hours contracts - but nor are they obliged to accept any work you offer.”
Of course if an employee regularly turns down work they will find they are not wanted. The same generally applies to agency workers. Agency working and zero hours contracts suit some employees and not others. At the moment I prefer agency working but if it stopped suiting me I'd look for a longer term contract
I would be interested to see some input from someone with solid employment law experience such as buildersmate.