The Blues co-owner told the B'ham Mail: "We are looking at one maybe even two continental stars who we will bring in on four to five-month deals.
"They are good players. If the deals come off they will cost a great deal in wages, and it will cost us more to arrange the loans.
"If they keep us up then there is the chance for them to sign longer deals at the club. To me, that is a great way to sign players. It keeps them hungry."
Sullivan added: "We do have to be careful in the transfer market but we are all hungry to achieve. The manager is well aware what money there is for players.
"But if the manager comes to us with a particularly exciting player then money will be made available. We do have policies, but we always try to remain flexible."