White House officials yesterday accepted a Republican challenge to turn the upcoming strategic arms limitation treaty (SALT) debate into a broad examination of the Carter administration's foreign policy.

Seeking to turn the GOP stance to the administration's advantage, White House press secretary Jody Powell said that Republican concerns about the U.S. defense posture should lead them to support President Carter's budget proposals for increased defense spending.

"If they share the president's view of the need to improve our defense capability, we would welcome their support," Powell said.

The Republican challenge to the White House was contained in a resolution adopted Saturday by a conference of GOP leaders meeting in Easton, Md. The resolution calls for making the Senate SALT debate the occasion for questioning the "total military and foreign policy relationship" between the United States and the Soviet Union.

White House officials said the Republican position came as no big surprise, but did serve to underscore the difficulty the administration faces in winning approval for SALT II, which is expected to be signed in a few months.

"If anyone here ever underestimated the difficulty of getting it through, I don't think anyone does now," one presidential aide said.

White House officials also took some comfort from the fact that adoption of the resolution was engineered by Senate Minority Leader Howard H. Baker Jr. (R-Tenn.), as an alternative to proposals that would have gone much further in laying down strict conditions for approval of SALT II.

Baker, a potential GOP challenger to Carter in 1980, was crucial to the administration's Panama Canal treaties victory last year. Baker and 15 of his Senate Republican colleagues voted for the treaties -- providing the two-vote margin of victory -- and they will be equally important in the SALT debate.

At the Easton conference, the Republican leadership took the position that consideration of SALT II must be "linked" to other aspects of Soviet U.S. relations and Soviet behavior around the world.

"Linkage is a fact of life," Baker said at the conference.

There was considerable irony in this, for Baker's assertion is virtually identical to the arguments that national security affairs adviser Zbigniew Brzezinski was making last year. Concerned about the presence of Soviet-supported Cuban troops in the Horn of Africa, Brzezinski argued that such Soviet activities would inevitably be linked to SALT II, possibly endangering its approval.

More recently, however, Brzezinski has dropped the linkage argument, adopting the dominant administration position that SALT II is so important it should be considered on its own merits, without regard to other aspects of Soviet-U.S. relations.

While Baker and other Republicans talked about linkage, White House officials predicted the final Senate votes will turn more directly on the treaty itself.

"In the end, whether or not they will vote on the basis of linkage remains to be seen," one presidential aide said. "They may use it as an excuse to broaden the debate."

Powell said the administration expects Senate members to vote on SALT II "without any personal or partisan motives."

If Republicans are concerned about such issues as the strength of NATO forces in western Euope, "the way to deal with it is to support our efforts to strengthen our position there," he said.

"It's hard to see how a vote on SALT would have any impact on these other matters," he said.