Despite objections from Secretary of State George P. Shultz, National Security Council officials were authorized to direct an office within the State Department that played a key role in aiding Marine Lt. Col. Oliver L. North's private fund-raising and public relations efforts for the Nicaraguan contras, according to documents released yesterday and a spokesman for the House Iran-contra committee.

Internal White House and State Department documents, released by the House committee, show that in 1983 Shultz unsuccessfully opposed a plan by then-national security adviser William P. Clark and one of his assistants to have the head of the State Department's Office of Latin American Public Policy, a unit created to win public support for the contras, report to the NSC. Clark and his assistant, Walter Raymond Jr., a former Central Intelligence Agency official, also succeeded in having a person they favored, Otto Reich, selected to run the State Department public diplomacy office, according to the documents.

During Reich's tenure, the public diplomacy office awarded more than $400,000 in noncompetitive contracts to International Business Communications (IBC), a company tied to North's secret contra support network. The State Department's inspector general previously criticized procedures used to award and monitor the contracts to IBC, a public relations firm headed by Richard R. Miller, former Reagan-Bush campaign aide. Reich, now U.S. ambassador to Venezuela, has denied that the office acted improperly.

Miller and Carl R. (Spitz) Channell, a conservative fund-raiser, have pleaded guilty to conspiring to defraud the government by using tax-deductible donations for contra military activities.

A spokesman for the House Iran-contra panel said yesterday that the documents, which are part of the committee's continuing probe of private contra fund-raising, show that North, who was fired from his job as an aide to the NSC, used the public diplomacy unit to indirectly run the Channel-Miller effort, which included lobbying, public relations and television ads for the contra program.

Other documents released yesterday suggest that the Channell operation considered a plan to "destroy" and "put . . . out of politics" former Rep. Michael D. Barnes (D-Md.), an outspoken contra aid opponent who chaired a key House subcommittee on Central America.

Handwritten notes that Iran-contra investigators have determined were prepared by an aide to " {Former Rep. Michael D.} Barnes trying to indict Ollie {North} -- wants to get at RR {Reagan} . . . . Destroy Barnes -- use him as an object lesson to others."

-- notes by aide to fund-raiser Channell

Channell said: "Barnes trying to indict Ollie {North} -- wants to get at RR {Reagan} . . . . Destroy Barnes -- use him as an object lesson to others."

Barnes, who was defeated in a three-way race for the Democratic Senate nomination in 1986, has contended that the White House played a role in his loss.

According to the documents, then-CIA Director William J. Casey had an active interest in efforts to win public support for the contras and in the summer of 1983 met with a group of private public relations specialists who urged a nationwide fund-raising and public relations effort "to sell a 'new product' -- Central America," according to a memo to Clark from Raymond.

In a May 25, 1983, memo to Reagan, Shultz asked to be the president's "sole delegate" in carrying out the Central America policy and requested that he and other State Department officials have the "dominant voice" in selecting personnel for department jobs.

In an unsigned White House memo that committee staff members say may have come from Reagan, Shultz was told that the existing procedure, in which Central America policy went through the NSC, would stand. "No single agency can do it alone," the memo said.