Britain's Liberty Steel, Europe's fourth-largest steelmaker, said on Monday it had submitted an updated offer for German conglomerate Thyssenkrupp's steel division.

The move comes about three months after Liberty Steel said it had made a non-binding indicative bid for the unit, which Thyssenkrupp has put on the block as part of a bigger group restructuring.

"This is an important step for Liberty demonstrating our binding commitment to the combination of the two businesses," Liberty Steel said in a statement, without disclosing any details of the offer. "Due diligence and our discussions with Thyssenkrupp have so far confirmed that a potential combination of Thyssenkrupp Steel Europe and Liberty Steel is the right answer from an economic, social, and environmental perspective."

Thyssenkrupp, which sources have said is also considering a spin-off of its steel division, said it would now carefully examine what Liberty Steel says is a "firmed up bid".