How to delete these records?

[p.durbar]

I have a SQL statement as follows:

select * FROM item left join channels on item.cid = channels.id where channels.id is null

(had to use this as it appears that 'NOT IN...' does not work on my providers version of MySQL)

This works fine and selects the correct records but i dont want to select 'em, i want to delete them but i've tried things like

Delete FROM item left join channels on item.cid = channels.id where channels.id is null

But this throws an error, how do i arrange the statement so it deletes those records?

Thanks