NEW YORK - New York City's St. Patrick's Day parade has stepped off without Mayor Bill de Blasio marching along with the crowds of kilted Irish Americans and bagpipers amid a dispute over whether participants can carry pro-gay signs.

The parade set off down Fifth Avenue on a cold Monday morning.

De Blasio's decision underscores political tensions over gay rights issues in the U.S. Boston Mayor Martin Walsh opted out of his city's parade Sunday after talks broke down that would have allowed a gay veterans group to march.

But Ireland's Prime Minister Enda Kenny joined the procession Monday, saying the holiday is about Irishness, not sexuality.

Parade organizers say gay groups are not prohibited from marching, but they aren't allowed to carry gay-friendly signs or identify themselves as LGBT.

Beer companies Guinness and White Plains-based Heineken pulled out sponsorship because gay and lesbian groups aren't allowed to march openly.