I was in a similar situation. We left the UK when DD was three and she is now six, in year one of a local non-English speaking school. We plan to return to the UK this summer and I am hoping the transition will not be too difficult for her. I taught her to read at home and she is probably not too far behind her peers in the UK, though we should have done more work on writing than we have.
We began with homemade flash cards featuring letter sounds and combinations of sounds, then started the Peter and Jane 'Keywords' books at level 1a. I made more flash cards to cover all the words in each new book we started (new words are listed at the end of each book) and made sure she was familiar with these before starting it to build her confidence when reading.
She made it to level 7 of Peter and Jane before becoming totally bored with them and refusing to read any more. By then though, she was able to decode words very well, even though Peter and Jane is not a phonics teaching series, and was reading her own choice of books. We have the ORT Read at Home books to level 4 which she has no problem with, but was never very interested in.
Peter and Jane are pretty dull, and dated, but I found that when combined with flashcard phonics teaching, they served her well. She still loves to read books with pictures, so isn't particularly interested in text heavy chapter books, but is a pretty confident reader (she's reading The Twits at the moment).
She always loved the flashcards and would get them out herself to play with all the time, whereas her interest in reading has taken longer to develop. Perhaps my choice of using Peter and Jane had something to do with that, but now she can read well she chooses the books that interest her.
I am not a teacher and I don't suppose that the way I have taught my DD in any way resembles the way she would have been taught at school in the UK. But without the know-how to teach her the proper way, I did what I could and she and I are both pleased with her progress. Hope this helps.