President Carter's new anti-inflation package is likely to contain a number of broad measures beyond federal budget cutbacks, possibly including further steps to tighten credit and new energy-conservation moves.

The president was said yesterday to be considering these and other options to accompany the spending cuts he said will propose to balance the fiscal 1981 budget. Budget-cutting was described as only one element in the plan.

Carter also reportedly intends to spend several days discussing any new proposals with affected constituent groups before formally unveiling the package, in an attempt to build a consensus and minimize political sniping.

The president's views were outlines to reporters during a meeting at the White House. Carter still has not decided what specifically to include in the package or when the proposals will be announced.

The status report came as Carter's top economic advisers continued their closed-door consultations with key House and Senate leaders about what spending reductions Congress might approve.

The group recessed in early evening to enable the administration's representatives to report to the president, and scheduled another session this morning. Sources said there were no formal decisions.

The two sides have been discussing a budget-balancing plan designed to trim $12 billion to $15 billion from overall spending and raise revenues by about $4 billion, possibly by recommending oil import fees.

There were reports of general agreement among lawmakers on a plan to reduce spending for state revenue-sharing. Sources said House and Senate members served notice on the economic advisers that they also wanted the defense budget to bear some cutbacks. Carter apparently did not even consider any cuts in his defense budget.

There also is substantial sentiment in Congress for trimming cost-of-living increases in Social Security benefits that are tied to the consumer price index, but the group reached no agreement on this issue yesterday.

Besides oil-import fees, revenue-raising moves being discussed include requiring banks to collect withholding taxes on depositors' interest and dividends, and increasing users' fees for waterways and aviation facilities.

The negotiators -- key House and Senate Democrats and top Carter economic and budget officials -- have been holding marathon sessions on the budget for three days.

It was not immediately clear what steps the White House was considering to tighten credit further. The president already has ruled out across-the-board credit controls that would crimp loans for autos and housing.

Officials say the administration may seek restrictions designed to dampen consumer spending, possibly cracking down on excessive credit-card use. Carter has met regularly with Federal Reserve Chairman Paul A. Volcker.

The president also was said to be considering setting specific targets for energy conservation, imposed state-by-state limits on gasoline consumption, limiting federal hiring and relaxing some federal regulations.

In yesterday's White House session, the president was described as rejecting contentions by critics, including Sen. Edward M. Kennedy (D-Mass.), that cutting spending sharply would not have much impact on inflation.

Kennedy charged on Friday that slashing outlays even by as much as $25 billion would reduce the inflation rate by only 0.2 to 0.3 percentage points. Several computer models of the economy have produced similar conclusions.

However, Carter was described yesterday as being persuaded that budget-cutting was important first as a signal to the public and other nations that the budget-balancing is needed to help calm the nation's financial markets, which have been in turmoil for weeks over the apparently worsening inflation outlook.

Carter's decision to spend several days holding consultations with key constituent groups before proposing his new anti-inflation package was intended to try to build broad-based support of his budget-cutting moves.

Carter is said to want the consultations to help persuade each key constituent group that it is not the only one being asked to make sacrifices, but is part of a national effort that involves across-the-board cuts.

The president also was described as still firmly opposed to wage-price controls. Carter has no authority to impose such restraints, and has told congressional leaders he would veto any such legislation.

Meanwhile, some lawmakers also were reported considering a new plan for enforcing any new spending cuts by asking House and Senate leaders to sit on any money bills that exceed their targets.

Under the budget process, Congress sets informal spending targets each spring, but usually raises them in the fall before they become binding ceilings. Any overspending enacted in between becomes part of the package.

The new plan, advocated by House Budget Committee Chairman Robert N. Giaimo (D-Conn.), would call on the House speaker and Senate majority leader not to send bills to the president for signature if they violate initial targets.

Before such bills were sent to the White House the House and Senate would be asked to enact separate legislation that would pare the affected programs to the initial targets.

Last year a Senate effort to trim spending back to spring targets was vetoed by the House.