Immigration Minister Scott Morrison has instructed departmental and detention centre staff to publicly refer to asylum seekers as ‘‘illegal’’ arrivals and as ‘‘detainees’’, rather than as clients.

The directive has been criticised as a ‘‘profound’’ shift by a leading asylum seeker agency, which says the new terminology is designed to dehumanise people.

In an email to detention centre staff, obtained by Fairfax Media, a department official writes: ‘‘The department has received correspondence from the minister clarifying his expectations about the department’s use of terminology. Accordingly we as [sic] that our service providers also adhere to the below instructions.’’

These include calling all people who arrive in Australia by boat ‘‘illegal maritime arrivals’’, a marked change from the more moderate language used under the previous government.