National monuments could no longer be erected on the Mall or the Ellipse, in Lafayette Park, West Potomac Park or Lady Bird Johnson Park or on Theodore Roosevelt Island under legislation approved yesterday by a House subcommittee that is hoping to check the spread of monuments across the nation's capital.

Commemorations in other national park land in the national capital region would be limited to those memorializing a war, a branch of the armed services or individuals dead at least 25 years.

The legislation would not affect five monuments already approved by Congress but not yet built, including a large one to President Franklin D. Roosevelt planned near the Tidal Basin.

Members of Congress and National Park Service officials have become concerned about a burst of requests to build monuments here to events and people, some of dubious national significance, when limited space is left. As a result, they are trying to put into law a policy on just who and what is deemed worthy of memorialization in the nation's capital.

There are now 111 monuments, memorials and plaques scattered about town, according to the Park Service's count, with only about 50 more spots left for statues in the core of the historic city -- where most groups insist their proposed monuments should be built.

The House Interior and Insular Affairs subcommittee on national parks and recreation took the first legislative step yesterday, and the full committee is scheduled to consider the bill Wednesday. Rep. Morris K. Udall (D-Ariz.), the committee chairman, had introduced the measure that was approved yesterday with two amendments.

The area where the monument ban would apply contains 37 monuments, including the Washington Monument, the Lincoln Memorial, the Jefferson Memorial and the Vietnam Veterans Memorial, a subcommittee staff aide said.

The restrictions on memorials in other park land here would apply, for example, to East Potomac Park, the George Washington Parkway and Rock Creek Park.

Sen. Malcolm Wallop (R-Wyo.), chairman of the Senate Energy and Natural Resources subcommittee on public lands, said at hearings in March that he wants to postpone any more monument requests until an overall policy on monuments has been established. A staff aide to Wallop said the senator plans to introduce his own bill on the issue but had referred earlier to the Udall proposal as a good starting point.

One amendment added yesterday by the House subcommittee requires that memorials be built within five years of congressional approval. However, this would not apply to the five approved but unconstructed monuments. In addition to the monument to FDR, Congress has approved monuments here to Lebanese-American poet Kahlil Gibran, the U.S. Navy, law enforcement heroes and Haym Salomon, who helped finance the American Revolution.

In this Congress, 17 memorials have been proposed. Three have been approved by the House: to Korean War veterans, women in the armed services and black Revolutionary War patriots.