Premier League clubs have been blocked from signing Ajax defender Jorrel Hato this month.
The youngster is a top target for Gunners chief Edu and has been linked with a January move to North London.
However, it's emerged due to Brexit laws, English clubs cannot sign Hato until he turns 18 in March.
As such any move from Arsenal will have to wait until the end of the season.
Hato, who can play at centre-half and left-back, has already made 40 appearances for Ajax.