'Verifying' documents required for Citizenship application

Hi, could any one explain the procedure prior to submitting documents required for Citizenship application? 
I understand that certain documents need to bear the seal of "Apostille" of the country where they were issued   
But I am confused by this instruction:-     "Full birth certificate of applicant duly legalized/ authenticated by  competent  authority (Ministry of Home/Foreign/External Affairs)"
Is the (Ministry of Home/Foreign/External Affairs) a Government department in Mauritius ?
Or is it a department in the United Kingdom that I submit the documents to before or after them being apostilled?  ......
Thanks to anyone who could advise

If you are from the UK you need them Apostilled by the DFA in the UK. You then present them in Mauritius for your Citizenship Application

I'm following this one for my application later.
Who's the DFA ?

Department of foreign affairs

Hi @whitesharkbait - thanks for your reply. I will send the documents to the DFA whilst I am in the UK.
My concern was that there was another part of the process that I needed to do such as visiting a Notary in Mauritius for his/her signature prior to submitting the documents at the PM's office with my application.