While the German club were able to fend off interest earlier this year, any admirers can activate a release clause in the 21-year-old's contract in 2022.
However, ESPN claims that Haaland and his representatives will ask for a contract worth £500,000 per week.
With the player available for half his market value, Haaland's camp may argue that whoever wins the race for his signature is still receiving value for money.
Haaland has netted 10 goals in the Bundesliga and Champions League during the current campaign. body check tags ::