The Black Cats have been frustrated in their attempts to add to their squad in recent weeks as a move for Fabio Borini has stalled, while Eduardo Vargas opted to join Queens Park Rangers instead of Poyet's men.
He told reporters: "If a player, especially a foreigner, has the choice of a club in London or here in the North-East in a similar situation, then he will pick London.
"When it comes to players we want, I won't tell them that Sunderland is on the outskirts of London. And I will be honest and tell them it is very windy here.
"I wouldn't want a new signing to come out on the training pitch with me for the first time in a gale not having been warned about it."
Sunderland face Manchester United in their next Premier League clash on Sunday.