President Barack Obama will propose a Buffett Tax on people making more than $1 million a year as part of his deficit recommendations to Congress on Monday.

Such a proposal is among several suggestions to a congressional super-committee expected to seek up to $3 trillion in deficit savings over 10 years.

White House Communications Director Dan Pfeiffer wrote in a tweet on Saturday that the tax would act as a kind of AMT (Alternative Minimum Tax) aimed at ensuring millionaires pay a minimum tax rate that at least matches middle-class ftax rates.

The Buffett Tax refers to billionaire U.S. investor Warren Buffett, who wrote earlier this year in The New York Times that rich people like him often pay less in taxes than those who work for them, due to loopholes in the tax code, even though they can afford to pay more.

Obama will lay out his recommendations in White House Rose Garden remarks at 10.30 a.m. (1430 GMT) on Monday and is expected to recommend steps to raise tax revenue, as well as cuts in government spending.

Those recommendations could include reforms of the Medicare and Medicaid government healthcare programs for elderly and poorer Americans. The White House has already said Obama will not recommend any changes to the popular Social Security federal retirement plan.

Congress is at liberty to ignore his suggestions, and Republicans, who control the U.S. House of Representatives, have said that they will not agree to any tax hikes.

INVESTOR SCRUTINY

If the president pushes for tax increases that stand little chance of being passed by a divided Congress, it may help him to blame Republican lawmakers for thwarting his plans at a time when the public's opinion of Congress has touched record lows.

But he is also under pressure to show leadership after rating agency Standard & Poor's recently lowered the U.S. AAA credit rating, and as investors scrutinize Washington for evidence it can curb the country's towering deficit and mounting debt.

The super-committee of six Democratic and six Republican lawmakers must find at least $1.2 trillion in deficit savings before the end of the year to avoid painful automatic cuts, and it is mandated to seek savings of up to $1.5 trillion.

Those savings are on top of $917 billion in deficit reduction agreed to in an August deal to raise the U.S. debt limit, and Obama wants the super-committee to go further.

Obama has separately urged the super-committee to consider $467 billion in tax increases on top of that goal to pay for a jobs bill he unveiled earlier this month.

He has repeatedly called on Congress to close tax loopholes for millionaires and billionaires as he seeks to draw a sharp distinction between himself and the Republicans before next year's election.

The Buffett Tax could help energize Obama's base by highlighting a feature of the U.S. tax code that allows the super-rich to pay lower tax rates than less wealthy Americans do, because much of that former group's income comes from capital gains earned from investments.

Those are taxed at 15 percent, compared with income tax rates of up to 35 percent for some middle-class Americans.

We're playing with fire if we don't agree at least on the minimum [in deficit cuts], said William Galston, a senior fellow at the Brookings Institution in Washington.

If we can't get to at least $1.2 trillion ... people outside the United States, to whom we are in the last analysis beholden, are going to reach conclusions about us that are going to make our jobs and our lives even more difficult, he said.