The deal, which was reworked from a 2014 pact, averts large duties on U.S. sugar imports of Mexican sugar and addresses industry demand for protection from cheap, subsidized sugar from its foreign supplier.
"I am glad all parties have agreed that the new sugar agreement is fair and addresses the shortcomings of the original deal," Ross said in a statement.
"I am hopeful that we can successfully implement this new agreement with the support and cooperation of all stakeholders."
The deal was agreed by the two governments on Wednesday and opened for public comments for seven days. Last week Ross and Mexican Economy Minister Ildefonso Guajardo announced an agreement in principle, but said U.S. producers did not support the deal.
In its first comments since the deal was initialed, the American Sugar Alliance, whose members include sugar farmers and producers, said it supported the "tightened" agreement.
"For too long Mexico was allowed to sidestep our trade law, but those days are over," the alliance's spokesman Phillip Hayes said in a statement, adding that stakeholders looked forward to ensuring the pact was "strongly enforced."
(Reporting by Lesley Wroughton; Editing by Joseph Radford)