A Potentially explosive confrontation over Gov. Cuomo’s tough new gun law was avoided over the weekend as 1199 SEIU, the hospital workers union, abruptly canceled a Thursday rally designed to challenge some 10,000 opponents of the governor’s measure, The Post has learned.

Weeks ago, the opponents announced that they would hold a rally Thursday. They said it would be one of the biggest protests ever at the state Capitol, with 10,000 or more in attendance.

But late last week, rally backers were startled to learn that 1199, which has strong ties to Cuomo, Mayor Bloomberg and the state Democratic Party, had joined with the Brady Campaign to Prevent Gun Violence to bus backers of the new law to a counter-rally...

As word of the planned counter-rally spread, the Albany police and aides to Cuomo agreed there was the potential for a serious confrontation.

Late Saturday afternoon, 1199 removed any mention of the rally from its Web site, and knowledgeable insiders said the pro-gun law rally was canceled.