MEXICO CITY (Reuters) - U.S. construction company Vulcan Materials on Monday rejected what it considers the "illegal expropriation" of its investments in Mexico and said it remains open to a negotiated solution with the Mexican government.

The company has been engaged in a years-long conflict with Mexico's government after officials ordered a halt to limestone quarrying at Vulcan's mining unit in the coastal state of Quintana Roo in 2022, alleging environmental damages by the company, which denies the accusations.

Mexican President Andres Manuel Lopez Obrador last week said that the site had not been expropriated, only closed, and that it would remain closed at least until he leaves office in October.

In a statement on Monday, Vulcan described the suspension of their operations as "authoritarian" and said it could not produce or sell materials "due to the arbitrary actions of the government of Mexico in order to force us to give up our important investments in the region."

Last year, Lopez Obrador laid out plans to offer 6.5 billion Mexican pesos ($391 million) to buy the land where Vulcan Materials operates and solve the dispute, but said the company did not want to sell the land.

"The truth is that at no time have we received a 'generous offer' to buy our property," Vulcan said on Monday.

"We were given an informal appraisal, without signatures and without details, that substantially undervalues our assets, including the limestone reserves of which we own under Mexican law, as well as the only deep draft port in the region."

($1 = 16.6440 Mexican pesos)