Paterson issued a memo earlier this month saying that gay New Yorkers who marry where it is legal will have the right to share family health care plans, receive tax breaks by filing jointly, enjoy stronger adoption rights and inherit property.
Paterson cited a February ruling in a New York Appellate Division court in which the judges determined that there is no legal impediment in New York to the recognition of a same-sex marriage.
While gay rights advocates hailed the move, the feeling was not unanimous.
State Senate Republican Majority Leader Joseph Bruno, who opposes gay marriage, questioned the constitutionality of Paterson's action, but said in a Thursday morning news conference that he hadn't yet seen the memo.
Bruno said he was surprised when he read news reports about the memo and plans to speak to Paterson. Bruno also noted the state's highest court has found gay marriage isn't legal within the state. The high court hasn't yet taken up the issue of whether gay marriages performed legally out of state are valid in New York.
"You have to understand that the court, the highest court here in New York state, made it very very clear that the only union that is legal in New York state, to perform a marriage ceremony, is between a man and a woman," Bruno said, citing a 2006 Court or Appeals ruling.
State Conservative Party Chairman Michael Long said Paterson should allow gay marriages to be recognized only if the Legislature legalizes gay marriage.
"The California judges overturned the will of the California people and Governor Paterson is apparently trying to do the same thing in New York," he said.
Earlier this month, the California Supreme Court ruled that same-sex marriage in the nation's most populous state is legal. The ruling overturned a voter-approved ban on gay marriage.
Paterson defended himself Thursday, saying: "This is not an end run around the Legislature. I am following the law as it always has existed."
He said failure to issue the directive would leave the state open to lawsuits claiming the state deprived gay couples of civil rights enjoyed in other states.
Of his critics claiming the action is unconstitutional, Paterson said they "should get a little better informed."
Massachusetts is currently the only U.S. state that recognizes same-sex marriage, but its residency requirements would bar New Yorkers from marrying there.
Canada is among the nations where gay marriage is legal. In California, gay couples will be able to wed beginning June 17 - unless that state's Supreme Court decides to stay its own ruling.
In a video shown at the Empire State Pride Agenda's spring dinner on Saturday, the governor said he directed the state agency measures as "a strong step toward marriage equality right here in our state."
"This is a milestone in the fight for fairness in New York," New York Civil Liberties Union executive director Donna Lieberman said in a statement. "Couples in New York who have never known true security for their families will be officially entitled to treatment by our state government that respects their rights."
Last year, the Democrat-led Assembly passed a bill to legalize same-sex marriage, but the Senate didn't take up the bill. A vote in the Senate is considered even less likely this year, a legislative election year in which the Republicans are hoping to cling to its majority by appealing in part to its more conservative base.
