Mexican sugar producers still want an investigation into suspected dumping in Mexico by U.S. fructose producers even after a U.S.-Mexico deal on access to the U.S. sugar market, the head of the Mexican sugar industry group said on Wednesday.

The sugar lobby last month said it had asked the Mexican economy ministry to investigate U.S. high-fructose corn syrup imports, saying there was "solid" evidence of dumping.

Mexico on Tuesday conceded to U.S. demands for changes in the terms of Mexican access to the lucrative U.S. sugar market, but U.S. sugar producers refused to endorse the deal.

The agreement would avert possible steep U.S. import duties on Mexican sugar and had been seen as lowering the risk of Mexico slapping its own import duties on U.S. high-fructose corn syrup as a retaliatory measure.

"This issue with the U.S. sugar industry is not over," Juan Cortina, the head of Mexican sugar industry group (CNIAA), told reporters at an event in Mexico City where he said the group would keep pressing for a fructose probe in Mexico.

The sweetener trade has been a long-standing source of disputes between the two countries that are preparing to start talks with Canada to renegotiate the North American Free Trade Agreement.

Mexican Economy Minister Ildefonso Guajardo on June 1 said he was reviewing the request by the Mexican sugar lobby to initiate the investigation.