The Dublin-based firm, which trades under the name of Cemex Ireland, confirmed the talks were about making an offer for the concrete supplier.
“Discussions are at an early stage and there can be no certainty that these will lead to an offer for Readymix nor as to the terms on which an offer, if any, might be made, ” said a brief statement.
Cemex is a majority shareholder in Readymix, which reported a loss of €6.6m for the first six months of the year in August.
The deficit was roughly in line with the first half of last year, when the company lost €6.9 million before tax.
Its operations lost €6.1m during the six-month period, before exceptional charges, which included €500,000 in rationalisation costs.