Newcastle have seen their latest offer for Deportivo La Coruna’s Albert Luque turned down by the Spanish club.
The Magpies are reported to have agreed terms with the 27-year-old, who was said to be keen on moving to England.
But Souness said: “I understand that our final offer was rejected, so I think this one’s finished.
“We have made a fantastic offer for the player. Really there is a limit on how much you can spend on one player.
“Our valuation is different to their valuation. He is their player right now. At this point, we think that’s too much.”
The latest setback continues a frustrating summer for Souness who has seen bids for Michael Owen, Nicolas Anelka, Luis Boa Morte and Mark Viduka all turned down.