Despite appearing to have been pipped to Sissoko's signature by Tottenham, Moshiri insists Everton made the decision to withdraw from negotiations and claims McCarthy was the major factor.
"[Moussa] Sissoko is a great player. But when I bought into Everton, I made it clear I was proud to join a family," a statement from Moshiri read.
"And we don't turn our backs on our own. Keeping James McCarthy was a priority and ultimately we could not proceed with a deal that would jeopardize his place at Everton.
"We wish Sissoko the best."