ST. PAUL -- Gov. Mark Dayton vetoed what he called a "mean-spirited, divisive, unMinnesotan" proposed constitutional amendment that would ban gay marriage, but his action will not stop the public from voting on it next year.

The symbolic veto this morning drew attention to the most publicized bill that passed the just-completed 2011 legislative session. The proposed amendment passed with mostly Republican votes to define marriage as between a man and a woman, effectively banning same-sex marriages.

The Democratic governor said that he plans to veto two anti-abortion amendments later today, also mostly supported by Republicans. One would ban abortions after 20 weeks, the other would forbid public funds to pay for abortions.

Another Republican bill likely will be vetoed Thursday. It would require Minnesotans to show a photo identification before voting.

The marriage amendment veto was a surprise since the state Constitution gives governors no say in making changes to the Constitution. However, Dayton said, since the amendment was presented to him in bill form he decided to make a statement and veto it.

He urged Minnesotans to reject the measure when they vote on it in November of 2012.

Lt. Gov. Yvonne Prettner Solon also spoke against the amendment, calling it a "travesty" that the only major piece of legislation to come out of the session is so divisive.

Openly gay Sen. Scott Dibble, DFL-Minneapolis, said both sides already are ramping up campaigns for next year.

"We've certainly taken a punch to the gut, but we are still fighting," Dibble said.

After announcing his amendment veto, Dayton convened a meeting of his Cabinet to discuss a government shutdown that he considers likely after he and legislative Republicans failed to reach an agreement for budget that begins July 1.

If no budget is signed into law by July 1, state government begins to shut down.

Don Davis reports for Forum Communications Co.