PHOENIX — Gov. Janet Napolitano on Friday rejected a legislative plan to freeze all new state and university hiring and promotions.

 In her second veto of the session, the governor called the measure “an unwarranted intrusion’’ into her power as the state’s chief executive. “One branch of government cannot exercise the powers and authority properly belonging to another branch of government,’’ Napolitano wrote. “That reason alone demands a veto of this bill.’’

 But Rep. Bob Robson, R-Chandler, said Napolitano may be the one who doesn’t understand the role of the Legislature.

 He said it would have been one thing if lawmakers told specific agency chiefs — who are part of the executive branch — not to do their jobs.

 This, Robson said, simply directed those agency chiefs not to hire new workers absent a showing of serious need because stat expenses are outstripping the taxes coming in. That, he said, fits within the Legislature’s constitutional role of adopting a budget.

 Napolitano also pointed out — and Robson acknowledged — the measure technically would not have done anything even if she signed it. That’s because it did not get the required two-thirds vote of each chamber to take effect immediately; bills without the emergency clause do not become law until 90 days after the legislative session ends.

 But Robson said she should have signed it anyway to show she agrees with the “sense of the Legislature’’ that drastic steps are needed. He pointed out the measure had support from some Democrats as well as Republicans. “I’m totally disheartened over the fact she didn’t ‘get it’ from the standpoint that this would have been a real opportunity for her to make a statement of saying, ‘Yes, I’m joining in a bipartisan way with the Legislature ... just recognizing the overall seriousness of it.’’

 The veto continues the war of words between the Democrat governor and the Republican leadership in the Legislature over how to make up what is shaping up to be a $1.2 billion deficit for the current fiscal year.

 GOP leaders have blamed Napolitano for not taking immediate action last fall when the projected deficit was only $600 million. Napolitano countered that she has a plan to bridge the gap, though that involves only about $150 million in so-far unspecified spending cuts with the balance made up with long-term borrowing and taking cash from the “rainy day’’ fund.

 Each day of inaction only makes the situation worse. On one side of the equation, state Treasurer Dean Martin said the pace of expenditures continues at the same rate it did when lawmakers approved a $10.6 billion spending plan last spring, before the projected deficit. And he said even the governor’s call on her agency chiefs in September to trim unnecessary expenditures has not made a difference. “We are still spending at a clip for that $10.6 billion original appropriation,’’ he said.

 Napolitano instituted her own hiring freeze for the agencies she controls, which do not include the universities and the courts, after the House passed Robson’s more far-reaching bill. At the same time, sales and income tax collections continue to lag far behind the projections lawmakers used when adopting that $10.6 billion plan.

 The result, said Martin, is the state will have spent the amount expected to be collected for the entire fiscal year possibly by the end of next month, leaving nothing to pay the bills for the balance of the budget year that ends June 30.

 Martin does, in fact, have some cash at his disposal, including the approximately $700 million in that rainy day fund as well as money in other special funds. But he cannot use that to pay the state’s day-to-day bills without authorization from the

 Legislature which would have to be approved by the governor. But given the projected $1.2 billion gap — which could grow by another $200 million — even that may not be enough to bring the budget into balance without spending cuts, deferred payments and borrowing.