WASHINGTON - US President Barack Obama made a major concession to Republicans Wednesday by calling for cuts in Social Security and Medicare during an ongoing budget battle in Congress.

Signaling a will to compromise, Obama said his new budget plan would cut Social Security, one of the government's big-ticket spending items, by $100 billions or more over the next decade.

"(The proposal) challenges the long-held Democratic notion that entitlements are sacrosanct," Republican Strategist Ford O'Connell told Xinhua in an interview Wednesday.

"The fact that the president is catching heat from both sides is relatively a good sign," he said, adding that Obama is seeking middle ground between budgets put forth by both parties.

"He's just not there yet," O'Connell said.

"He's trying to prep his own party for that (cuts in spending) but at the same time he's hitting the Republicans pretty hard on the revenue side," he added.

For their part, if Republicans want to steer the president more in their direction, they will have to convince Obama of their belief that smart deficit reduction will lead to private sector job growth and a stronger dollar, O'Connell said.

But Obama's concessions may not be enough to win over Republicans, as the budget proposal also contains tax increases on upper earners, something GOP lawmakers are dead set against. Some analysts and media predict the bill will be dead on arrival.

While the plan would slash spending over the next decade by $1.2 trillions, it would also include tax hikes for higher earners.

According to a CNN poll released Monday, just 38 percent of respondents said they approve of the president's handling of the federal deficit, making the issue his lowest-scoring in a list of nine about which respondents were questioned.

Obama's budget proposal is the latest round in an ongoing budget war and comes on the heels of the fiscal cliff - a mix of spending cuts and tax increases - and the sequester - a spate of automatic spending cuts that kicked in on March 1.