HITC Sport understands that Fulham's captain has made the request official.
HITC Sport revealed Middlesbrough's opening offer for McCormack earlier this month and since then he has not trained with the West London club, and missed the weekend's defeat to Hull City.
Fulham rejected Boro's first offer and have insisted that they do not want to sell, but the Teessiders have refused to give up on the Scottish international and have maintained contact.
Now McCormack has made it quite clear to his bosses that he does not want to stay at Craven Cottage and wants to move to The Riverside, where he believes he will achieve his dream of playing Premier League football.
With that HITC Sport can reveal that McCormack put a written request to Fulham chiefs on Thursday morning and now he is hoping that an increased bid from Boro - which is expected before the weekend - will persuade the club to sell.
Boro are ready to go up to £12 million plus Kike to land the player, but as Fulham are under a transfer embargo they cannot use the money to sign somebody permanently, they can only loan a player - which has hampered the North East club's bid.
HITC Sport understands that the final decision will rest with Fulham owner Shahid Khan.