Clairmont, a talented 17-year-old player, has recently joined West Ham U18s. Despite this, he is still contracted under scholarship terms with Arsenal, as reported by Jeorge Bird's Arsenal youth website.
The winger has trained with the first team squad under Arsenal manager Mikel Arteta.
But he is now chasing a contract with the Hammers.
Clairmont has managed just the five appearances for Arsenal's U18s after his promotion last year.