Nicolas Anelka has announced on his Twitter account that he is to leave West Brom with immediate effect.
Mauricio Pochettino expects to be at Southampton next season and is looking forward to working with chairman Ralph Krueger.
Bayern Munich have confirmed Mario Gotze will join them in July.
The Bundesliga champions are prepared to meet the Germany attacking midfielder's £32million release clause in his contract with Borussia Dortmund.
Bayern announced the signing in a statement on their official website after Dortmund earlier revealed the player had told them he wanted to make the move.
The Dortmund statement read: "Mario Goetze's agent Volker Struth told us a few days ago that the player wishes to make use of his release clause and on July 1, 2013 move to Bayern Munich."
Dortmund chief executive Hans-Joachim Watzke said: "We are obviously disappointed beyond measure, but emphasise that both Mario and his advisers have behaved within the terms of the contract."