The Carter administration has under serious consideration as part of its evolving urban policy a new program of grants to the states that could total more than $1 billion over two years.

The federal government would provide up to $500 million a year in special "incentive grants" to states that develop plans to shift more of their own resources to their aging, often rundown cities.

Eventually, however, probably in the third year, every state would be required to develop a plan to aid its cities or risk losing some of the general revenue-sharing money it now receives from the federal government.

According to White House officials, some form of this proposal is almost certain to be included in the final version of President Carter's long-promised urban policy, now scheduled to be unveiled in March.

Carter is likely to find the proposal attractive because it would provide a vehicle to achieve two of his stated goals - involving the states directly in a national urban policy, and curtailing the flow of more than $2 billion a year in general revenue-sharing grants to the states.

During his election campaign, the president opposed general revenue-sharing grants to the states - which give the states broad discretion in the use of the money - in favor of larger direct revenue: sharing grants to financially troubled cities.

Understandably, according to White House officials, state governments find the possibility of $1 billion in new grants attractive but are notably less enthusiastic about the eventual risk to their general revenue sharing.

When White House officials briefed staff aides at the National Governors' Association on the proposal last week, the revenue-sharing aspects drew the most skeptical questioning.

As more states enter the competition for incentive grants, beginning in the second year, the proposal envisions that the money available for this purpose would be supplemented from the general revenue-sharing funds. Thus, states that come up with acceptable plans could expect additional financial aidfrom the federal government, but at the expense of their sister states.

This aspect prompted one governors' association aide to tell White House officials the plan would "set the states at each others' throats."

White House officials have already backed off somewhat on the revenue sharing. Early drafts of the plan suggested that eventually all the money that now goes to the states as general revenue sharing would be converted into grants to encourage state help for the cities. But now White House officials are saying that no state would lose all of its general revenue-sharing money even when all are required to have plans to aid their cities.

The nation's big cities have their own problems with the proposal. They acknowledge a role for the states in a national urban policy, but skepticism lingers about the treatment they can expect from state legislatures, which until reapportionment became mandatory were often dominated by rural interests.

Seeking to clam those fears, the administration has promised the cities that in no case will money now going directly into urban programs be used for the grants to the states.

White House officials argue that, because the states exercise so much fiscal and governmental control over their cities, no national urban policy can hope to succeed unless the states are a part of it.

Among the steps they say the states could take to help their cities, and thus qualify for the special federal grants, are to increase state revenue sharing to the cities, target public works and other investment program into depressed urban centers, and reform property tax laws that often retard redevelopment of older city neighborhoods.

Tomorrow is the White House deadline for comments by government agencies and others on this and other aspects of the urban policy. The president is expected to receive a "decision memorandum" from his domestic policy staff in early March and to announce his decisions by mid-March.