The Pentagon has offered to fund more C-130 aircraft for the Air National Guard to placate state governors complaining about proposed budget cuts that scale back fleet and personnel, officials said Monday.

Facing growing political pressure in an election year from governors and lawmakers in Congress, Defense Secretary Leon Panetta and Air Force leaders have come up with a compromise that would shift $400 million to the Air National Guard to fund 24 C-130 transport planes, defense officials told AFP.

To pay for the change, money would have to be cut from the Air Force's budget for active duty airmen and aircraft, the officials said.

The move is unusual as the Pentagon usually makes no major changes to the gargantuan defense budget once it is submitted to Congress, and tends to hammer out compromises with lawmakers in Washington instead of state governors.

But the proposal came after Panetta and top officers held a series of meetings with governors on the issue in recent months, said defense officials, who spoke on condition of anonymity.

A bi-partisan "council of governors" from various states had proposed a much more dramatic revision of the Air Force budget, moving more money and planes from active duty forces to the Air National Guard, including F-16 fighters, aerial refueling KC-135 tankers and unmanned drone aircraft.

Top defense and Air Force officials rejected the governor's proposed changes, saying they would pose a threat to combat readiness and place a strain on active duty airmen who they say have had insufficient time back home between frequent deployments, defense officials said.

The compromise offered by the Pentagon was partly based on the idea that C-130 cargo planes are in keeping with the mission of the Air National Guard in US states, where governors turn to the Guard and the reserves to respond to natural disasters.

"We believe this proposal is very much in keeping with the national defense requirements laid out in our strategy and the public safety concerns expressed by the Council of Governors," Pentagon spokesman Captain John Kirby said in an email.

"These aircraft play a vital role in our support to civil authorities, particularly in the event of natural disasters. It's the right thing to do."

The Defense Department has requested $613 billion for fiscal year 2013, essentially holding spending steady after a decade of massive budgets.