In an unprecedented challenge to supervision of its broadcasts, the Voice of America has come into an open conflict with the State Department over VOA foreign news gathering operations.

For the first time the leadership of the government-controlled radio and its parent organization, the U.S. Information Agency, has publicly questioned State Department restrictions imposed on VOA foreign correspondents.

At issue is the radio's lack of independence and the problem of its credibility with millions of listeners world-wide.

For years, the issue of State Department control over VOA broadcasting has been brewing in various bureaucratic forums here as the radio and its supporters privately sought to carve out a greater degree of independence and increase is credibility.

But a recent State Department ban on the radio's proposed in-depth coverage of Western Sahara problems has brought the split into the open, with senior USIA officials contesting the decision. Specifically, the department prohibited a VOA correspondent from talking with Polisario gurgillas fighting for an independent Western Sahara.

Added important was seen in the fact that the conflict coincides with current government reoganization proposals moving through Congress that would bring the USIA and the VOA under greater control of the State Department.

Both USIA Director John Reinhardt and VOA Director R. Peter Straus have openly contested the State Department position in an unusual frontal challenge which may have long-lasting impact on VOA broadcasting policy.

Straus has named a high-level panel to study the question of whether a correspondent for a government-run news agency can or should operate with the same freedom as a journalist for a private news organization.

With the USIA and VOA to be linked more closely to the State Department under the reorganization proposals, the row over the role of the correspondent takes on more meaning for the future of the radio and its parent agency.

Straus said in an interview that he plans to name three outside experts within the next two weeks to make an in-depth study of the role of the VOA's correspondent corps, which numbers 16.

"The crucial question that remains is the role of 16 people - the foreign correspondent corps," Strauss said.

"It lies at the crux of the problems that arise when a news organization is also a government agency: can a reporter be independent if he receives security clearance, carries an official passport is paid from government funds and has high 'visibility' in many areas of the world just because he is a VOA correspondent?"

The tug between VOA and the State Department is a long-standing issue, but Congress last year came down on the side of "independence" of the voice's news operations in order to increase its credibility for millions of listeners.

President Carter endorsed this concept as a candidate and in his recent message to Congress that would create the new International Communications Agency, of which VOA is to be a part.

According to Reinhart, director of USIA, the latest round in the State Department-VOA tug of war arose when VOA correspondent Doug Roberts proposed to go to Algeria, Morocco and Mauritania to talk to "all parties" involved in the struggle over possession of the Western Sahara. He proposed to do a long backgrounder or analytical piece on the situation, Reinhart said.

The State Department, according to well-informed sources, invoked its control over all U.S. officials when traveling abroad and said Roberts could not meet with members of the Polisario guerrillas.

State Department spokesmen refused to comment on the issue.

Reinhardt and Straus said they both fought the issue with the State Department but Deputy Secretary of State Warren Christopher upheld the ban.