The Austrian is heavily linked with leaving Stuttgart in the ongoing transfer window and has several top clubs across Europe vying for his signature.
Bundesliga giants Bayern Munich and Dortmund have Kalajdzic on their transfer radars, while Premier League outfit Tottenham, who want another striker, are also keen on him.
Spurs boss Antonio Conte wants to sign a back-up and potential long-term successor for Harry Kane this summer and they have zeroed in on Kalajdzic.
The north London giants are stepping up efforts to secure a deal for the Stuttgart man but are facing strong competition for his signature.
And according to German daily Bild, Dortmund will also intensify efforts to seal a deal for Kalajdzic from 20th June onwards.
Kalajdzic is currently away on international duty with Austria which will be followed by his summer holiday, and Dortmund will push on with negotiations for the player, once he returns.
It remains to be seen whether Tottenham will manage to win the race for Kalajdzic with the summer window now in full flow.
