If youre doing the whole contextual writing of a piece or creating a mini bio of him for say a gcse sketchbook?... then be very vague with how you classify him, instead focus on his work and be very descriptive and critical.
Monet was a french impressionist who specialised in plein-air landscape painting.. which basically just means outdoor nature paintings. Although this was his specialism, i wouldnt directly state that he was an abstract landscape artist... Although if that is your interpretation of his work, anything goes. Write from the first person, as if its what YOU as the viewer think, not what you might have read.
: )