Washington — With little debate, the Senate Foreign Relations Committee on Wednesday gave an overwhelming vote of approval for William Wilson to become the first US ambassador assigned to the Vatican in more than a century.
The endorsement smooths the way for full Senate confirmation within the next two weeks, unless Sen. Jesse Helms (R) of North Carolina decides to put a hold on the nomination.
''I just can't bring myself to vote for any ambassador to the Holy See,'' said Senator Helms to the Foreign Relations Committee as he cast the only vote against Mr. Wilson, a California entrepreneur and friend of President Reagan. Helms said he opposed recognizing anything ''other than another government.''
Sen. Charles H. Percy, chairman of the foreign relations panel, said that 107 countries have ambassadors at the Vatican and that the United States now has an envoy. ''We have no oversight over the position as envoy,'' said the Illinois Republican, explaining that the Senate would have more control if the post were upgraded.
Senator Helms, who has frequently taken one-man stands on the Senate floor, said earlier this week that he had not decided whether to pull out all of the parliamentary stops to block Wilson's confirmation. ''I haven't made up my mind, '' he told reporters.
The North Carolina senator, who praised Wilson personally as a friend and ''one of the finest human beings I've ever known,'' showed some signs that he would not relish leading the opposition.
Helms pointed to the House and Senate appropriations committees which have not yet given the Department of State permission to reprogram $351,000 to pay for expanding staff and office space for a Vatican embassy. ''The real story is what's happening in both House and Senate appropriations,'' Helms said.
''My only regret,'' said Helms, ''is there was not a full-fledged discussion'' when the Senate passed the law that permitted establishing diplomatic ties with the Holy See.
Since 1867 federal law had forbidden the US to spend money on an embassy at the Vatican. That law was erased last November, after the Senate passed an unprinted amendment to lift the ban. The amendment, passed without hearings, had the strong backing of President Reagan. He has already signed the bill into law and established formal diplomatic ties with the Holy See.
Despite lobbying by the White House, neither House nor Senate appropriations panels has yet given the green light for spending additional funds for the Vatican embassy. Opponents of the plan, including several religious groups, will have a chance to speak out March 5 at a Senate appropriations hearing. Committee chairman Mark O. Hatfield (R) of Oregon has indicated he will also question Secretary of State George P. Shultz when he appears before the panel on March 28 .
The House Appropriations Committee held a hearing last month but has not taken action yet. However, even if the congressional committees reject the plan to spend money on the Vatican embassy, it is not clear that they could legally forbid the State Department from using its funds for the Vatican embassy.
Opponents of establishing formal ties with the Roman Catholic Church at the Vatican have cited favoritism toward one church as well as constitutional objections. The Southern Baptist Convention this week passed a resolution calling the naming of an ambassador to the Holy See a ''dangerous precedent.''
Some members of the opposition are already conceding defeat in the legislature and making plans to take the issue into the courts. A spokesman for Americans United for the Separation of Church and State said that ''a lawsuit is almost a certainty'' if the Senate, as expected, confirms the Wilson appointment.