Thyssenkrupp said the decision was made after no agreement could be found with Liberty.
"We opened the door for negotiations, but in the end our ideas about the corporate value and the structure of the transaction were far apart," CEO Klaus Keysberg said in a statement.
In the press note, Thyssenkrupp said it would now continue to drive forward a "sustainable position" for steel on its own.
Liberty Steel submitted an updated, non-binding offer to Thyssenkrupp to acquire Thyssenkrupp Steel Europe earlier this year and Keysberg said in a press call last week that Liberty was the only sale partner considered. Keysberg however did stress then that a "stand-alone" solution for the steel unit was still being discussed where Thyssenkrupp would split off the unit.
This was the second attempt to merge Thyssenkrupp's steel unit following the collapse of merger talks in 2019 with Tata Steel Europe. Tata Steel Europe meanwhile also had a second attempt to merge its steel unit, but potential partner, Swedish steelmaker SSAB, called off the talks earlier this year.
The news of the Thyssenkrupp-Liberty talks collapse is likely to further stir market chatter regarding if the European steel industry will see other constellations or possible mergers. Market sources told S&P Global Platts that SSAB might be a better fit for Thyssenkrupp than Liberty, based on customer markets and products.