Sunderland boss David Moyes says he hopes to buy this month.
However, he has warned supporters that a combination of the club's finances and the perilous league position will make it difficult to strengthen his squad.
Moyes said: “We are looking, but saying we are looking doesn't mean we are in there, spending millions and millions.
“But are we looking? Yes we are.
“But, in our position, it is not that easy to attract players to the club."