House-Senate conferees yesterday approved arms constraints that would ban further moves by the Reagan administration this year to exceed weapons limits in the unratified SALT II treaty or to conduct "Star Wars" tests in violation of a narrow interpretation of the Antiballistic Missile (ABM) Treaty.

The compromise arms-control package also would continue the moratorium on tests of antisatellite weapons against objects in space but drops a House demand for a ban on all but the smallest nuclear tests.

The arms curbs were approved as part of the defense authorization bill for this year. It is expected to be submitted to the House and Senate for approval later this week.

Other parts of the measure, authorizing as much as $296 billion for military operations and procurement for fiscal 1988, were approved by conferees last week.

Although President Reagan had threatened to veto the bill if it included tougher SALT II and ABM restrictions, conference leaders said they expect him to sign the compromise, most of which was worked out in consultation with Defense Secretary-designate Frank C. Carlucci.

"It is probable that the president will sign the bill, but he has to look at the language," said a senior White House official, who added that the agreement "sounds right" on the surface.

In characterizing the conference agreement, lawmakers were careful to avoid victory claims that might antagonize the White House.

"The White House got what it wanted," House Armed Services Committee Chairman Les Aspin (D-Wis.) said. "Nothing in the law will order it explicitly to endorse SALT or the narrow {ABM} interpretation.

"We got what we wanted. The administration will do nothing in the coming year that will violate the narrow interpretation, and it will stabilize the strategic {weapons} launcher count rather than continue its buildup," he said.

If Reagan signs the bill, which also includes a $16 billion cut from his defense spending request and a substantial reordering of military priorities, it would temporarily defuse a dispute that has inflamed relations between the White House and the Democratic-controlled Congress for most of the year.

It would also clear the decks of a potentially embarrassing domestic dispute over arms control just as the United States is planning for Reagan's summit meeting with Soviet leader Mikhail Gorbachev here Dec. 8-10.

Conferees of both parties said concern about the summit was a major reason why Congress reached terms with the administration on arms provisions.

Conferees indicated that prospects appear good for passage by both chambers, although Sen. Jesse Helms (R-N.C.) was soliciting support yesterday for an effort to challenge the agreement on procedural grounds. Helms said he would pursue the challenge only if enough senators support him.

Under the agreement, both chambers would drop language barring the administration from using a broadened interpretation of the 1972 ABM pact to conduct expanded tests of its space-based Strategic Defense Initiative (SDI) or from deploying strategic weapons that would further violate SALT II limits.

Instead, Congress would hold the administration to a testing schedule that it submitted earlier this year, which contemplates no testing in violation of the traditional narrow ABM interpretation. In addition, acquisitions for tests prohibited under the narrow interpretation would be barred.

Making no reference to either of the disputed treaties, the agreement also denies funds for overhaul of a Poseidon submarine, the USS Andrew Jackson, in order to keep the current level of nuclear missile launchers through the current fiscal year.

Conferees indicated that further efforts to limit deployments under SALT II will depend on Soviet compliance efforts and progress toward a new strategic-arms agreement.