"We have known these rumours for many years," Zorc said: "We plan at least until the end of the season with him."
Pulisic is wanted by Liverpool, whose boss Jurgen Klopp brought him to Dortmund, and Chelsea.
A fee in the region of £70m, has been mooted but that is likely to come down the closer it gets to 2020. Pulisic said he was open to a move to the Premier League last week.
Where Zorc’s comments leave Chelsea remains to be seen. Express Sport understand boss Maurizio Sarri is planning to splurge more than £200million in January now the club have got the threat of a two-year transfer ban hanging over them - and Pulisic is one key target.
Liverpool and Chelsea are interested in Christian Pulisic (Image: GETTY)
Liverpool and Chelsea have both made Christian Pulisic a transfer target (Image: GETTY)
Liverpool and Chelsea have both made Christian Pulisic a transfer target (Image: GETTY)
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FIFA have recommended the Blues receive a four-window transfer ban following an investigation into them signing under-age foreign players.
It means Chelsea will now work around the clock in January to bring in a number of targets before the ban hits.
They are ready to go head-to-head with both Manchester United and City to sign £50m-rated Brazilian wing-back Alex Sandro, 27, from Juventus.
Sarri may also return to his former club Napoli and pay £50m for right-back Elseid Hysaj, 24. They are also looking to invoke a £40m buy-back clause in the deal that took central defender Nathan Ake to Bournemouth.