(CNN) -- Bayern Munich completed the $50m signing of Spanish midfielder Javi Martinez from Athletic Bilbao, on Wednesday. Martinez, part of the victorious Spain squad at the 2010 World Cup and the 2012 European Championship, had a $50m release fee in his Bilbao contract, but was required to pay the amount himself, which created huge tax liabilities for the player and complications for the German club. Bayern's chairman Karl-Heinz Rummennigge described the transfer as "very complicated" and accused Bilbao of "refusing to cooperate from the very first day" of negotiations. "We've had tax and legal problems to solve over the last few days, but fortunately we've succeeded," he said.
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Javi Martinez completes $50m move from Athletic Bilbao to Bayern Munich
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Bayern chairman accuses Bilbao of "refusing to cooperate" with German club
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Tottenham Hotspur complete the signing of Moussa Dembele from Fulham
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Former Bayern goalkeeper Michael Rensing moves to Leverkusen
"We are delighted to announce that we have reached agreement with @placeholder for the transfer of Mousa Dembele," Tottenham announced on their website.