The Bundesliga side want £37m for the Germany forward and are not keen on a player-plus-cash deal.
"You should ask Mr Wenger, call him. There's no contact with Arsenal or any other club," said Heldt.
"I cannot exclude the option we will sign Cristiano Ronaldo. I don't need to talk about this.
"I understand why you are asking the question but all the topics you mention need to be addressed in London."
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