ALBANY – Governor Pataki yesterday vetoed $2.9 billion from what he said was a fiscally irresponsible $115.5 billion state budget approved by lawmakers last week, setting up a possible court showdown with the Legislature.

The lame-duck Republican governor, eyeing a 2008 run for president, rejected as unconstitutional the “rebate” checks to property taxpayers that would typically be about $400 and a $330 child tax credit for state income taxes. He also cut $200 million intended mainly for the local pet projects of election-bound lawmakers.

Mr. Pataki said his vetoes bring the budget to $112.8 billion, still $2.2 billion more than he proposed in January.

“The legislative budget as adopted created very real fiscal problems for New York,” Mr. Pataki said, citing estimates of a $6 billion deficit next year under the lawmakers’ plan. “We will be bringing down the level of spending from the legislative budget significantly and we will be protecting the taxpayers and finances of this state.”

Mr. Pataki cut $650 million in Medicaid funding that the legislature had appropriated, though spokesman David Catalfamo said overall funding for the program will still rise by $521 million. “It’s no secret our health care facilities and emergency rooms are facing a critical shortage of doctors and nurses,” the Healthcare Association of New York State president, Daniel Sisto, said. “The funding Governor Pataki vetoed would have helped provide those staff. He has compounded the crisis and put every community at greater risk.”

One of Mr. Pataki’s spokesmen, Scott Reif, said that under the budget, New York will continue to spend more money than any other state on providing health care.

Mr. Pataki also eliminated $34.2 million in funding this year for a state program that pays for nursing home care for one spouse if the other one refuses to foot the bill, no matter how well off he or she is.

The governor said one of his vetoes restored his proposal to require college students to take 15 credit hours – instead of 12 – to secure their full financial aid under the state Tuition Assistance Program that helps hundreds of thousands of students. Mr. Pataki also cut about $107 million from the operating budgets for the State University of New York and City University of New York and around $400 million in capital projects at the schools.

The cuts in education were immediately criticized by the president of the New York State United Teachers, Richard Iannuzzi, who called on the legislature to swiftly override Mr. Pataki’s “cruel and unusual” vetos. “These are the desperate acts of an administration yearning for relevance,” Mr. Iannuzzi said. “If you’re a homeowner with two school-aged children, the governor just took $1,000 out of your pocket.”

The Assembly speaker, Sheldon Silver, and the Senate majority leader, Joseph Bruno, said they will wait until after the Easter-Passover break to consider overrides of the vetoes and any legal action.

“I think he is heading in the wrong direction,” Mr. Bruno said. “I think that is just unfortunate to deny a tax rebate. It’s not a prudent thing to be doing at this stage. We’re talking about $1.6 billion. This is critically important for the taxpayers of New York State.”

Mr. Pataki has said recent court rulings give him the constitutional upper hand over the Legislature when crafting budgets.

A professor at Albany Law School and an expert on the decisions of the state’s highest court, Vincent Bonventre, said the law appears to be on Pataki’s side.

“Anything that smells, tastes, or feels the slightest little bit like a budget matter, the governor has imperial power over it,” he said. “It doesn’t seem to me there is anything legally wrong with a chief executive vetoing an action of the Legislature that he believes to be unconstitutional. Whether this is pure politics is totally beside the legal point.”

Mr. Pataki said lawmakers could only restore about $650 million in programs he vetoed for nonconstitutional reasons. The rest of the spending, he said, is simply illegal. Mr. Pataki said he only issued the vetoes for that spending because he believed in a “belt and suspenders” approach to dealing with the Legislature.

For the second straight year, Mr. Pataki axed a legislative measure to bring two energy efficiency programs, and the money that goes with them, under the control of lawmakers. Currently, the money is controlled by the Pataki administration.