you can offer them contracts already from like 10am on the 31st December :)
 
Because English clubs cannot sign other English club's players on pre-contracts until June 1st. You will either have to buy him or wait until June.
 
as andy says above you are an english club so you must wait until the player from another english club is out of contract before offering them a contract. You can only approach players from foreign clubs after january 1st
 
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