Poland coach Lukasz Piszczek caused a stir last week when he hinted that Dortmund's Polish trio of Lewandowski, Blazczykowski and Lukasz Piszczek will all be moving on, naming clubs in England and Spain as likely targets.
Watzke is having none of it, though, and insists the trio will still be representing his club again next season.
"I know Smuda very well and he has a high opinion of us and we have a high opinion of him," he said.
"We talk a lot and I cannot imagine that he said what he said in the way it was reported.
"I don't care in any case. I don't know how often we have got to stress that Robert Lewandowski will certainly be staying with us.
"And 'Kuba' (Blaszczykowski) has been here five years and he is happy with what he has got here. I am confident that he will stay."
Watzke does not fear losing more of his side's key players after Shinji Kagawa's move to Manchester United and says the situation with the Polish trio is completely different.
"With respect, Manchester United did come looking for him," he told the Ruhr Nachrichten.
"He was given the chance to fulfil a childhood dream. But we are not forced to sell anybody for financial reasons."
Watzke also insisted Dortmund would not be paying over the odds for their transfer targets just because they have sold Kagawa and have money in the bank.
The Westphalians are currently chasing Stuttgart forward Julian Schieber.
"Julian Schieber has a certain value in our eyes and we would be prepared to pay that," he said.
"But we are not going to do anything crazy, not with any player. We continue to be cautious with our money."