A lot depends on the size of the tree and the number of fruits. We usually rely on people like Patty (hoosierquilt here) to answer these questions; but I think she is currently fully occupied as wedding planner. As always, if you post photos you will get quicker and better advice.

Yes, photos would be helpful. But, at this point, it's getting past navel season, and most mandarins as well (some are later, you don't mention the cultivar). If they are not growing and are still small and green, and were part of this year's crop (not off-season), I would remove them. Is your tree starting to blossom yet?

Patty S.

this is the clementine

this is the navel, both trees about 4 years old.
Yes, there's some disease/problems on the leaves which
started early winter - I thought winter was going to take care of that, but winter was very mild.

clementine fruit - there's quite a bit of such small fruit
on the tree. In december last year I picked the ripe clementine mandarins - not sure if these were so tiny that I didn't see them
then - anyway, didn't see any blossoms inbetween - it was a mild winter.

here's an example of the navel fruit - it's about 2cm diameter.
The clementine fruit is much smaller - less than 1cm diameter.

i see no need to remove them, you've got a head start on fruit production for this year. citrus are tropical and generally have 2 crops, but in cooler climates with cold winter temps they usually only have 1 crop.

if there's too many fruits, the trees will self thin.

OK, thanks ! - good to know, will leave all fruit from now on .