ST. PAUL — General Mills said Thursday it opposes a proposed Minnesota constitutional amendment to bay gay marriage, the largest company in the state to come out against the measure so far.

“We do not believe the proposed constitutional amendment is in the best interests of our employees or our state economy — and as a Minnesota-based company we oppose it,” Ken Charles, vice president of global diversity and inclusion for General Mills, wrote in a public blog post on the company’s website. “We value diversity. We value inclusion. We always have . and we always will.”

Minnesota already bans gay marriage by statute, but gay marriage opponents have said putting the ban in the state constitution would make it harder for courts to undo it. Voters will decide the issue in November.

Minnesota for Marriage, a main group pushing for the amendment’s passage, accused General Mills of “pandering to a small but powerful interest group.”

“By taking this position, General Mills is saying to Minnesotans and people all around the globe that marriage doesn’t matter to them,” Chairman John Helmberger said in a statement.