(Adds Hollande comment)
PARIS, March 9 (Reuters) - Swiss-French cement maker LafargeHolcim should think twice about supplying cement for the wall U.S. President Donald Trump plans to build on the border with Mexico, French Foreign Minister Jean-Marc Ayrault said on Thursday.
Trump's plan has caused a diplomatic crisis with Mexico, and in an interview with Agence France Presse earlier this week, LafargeHolcim's chief executive Eric Olsen said he was prepared to supply the materials for it.
Officials at LafargeHolcim could not be immediately reached for comment regarding Ayrault's remarks.
"It (Lafarge) should reflect upon what its interests are. There are other clients who will be stunned by this," Ayrault said on France Info radio.
"Lafarge says it doesn't do politics. ... Very well, but I would say companies ... also have social and environmental responsibilities."
French President Francois Hollande also urged caution when asked about LafargeHolcim's readiness to supply the wall project.
"I think there are markets where one must be cautious before declaring one's candidacy," Hollande told a news conference on the sidelines of a European Union summit in Brussels.
Olsen was quoted as saying in the AFP interview: "We are the number-one cement group in the United States. ... We are here to support the construction and development of the country. ... We are not a political organisation."
LafargeHolcim last week acknowledged that one of its cement plants probably paid protection money to armed groups in Syria to keep the factory running, calling the payments reported by news media "unacceptable" in hindsight. (Reporting by Marine Pennetier in Paris and Jean-Baptiste Vey in Brussels; Writing by Andrew Callus and Adrian Croft; Editing by Jonathan Oatis)