South Africa charged today that the Security Council's refusal to grant a hearing to the internal political party in Namibia "has stripped away the last vestige of any claim the U.N. might have had to being an impartial arbiter of the future of the territory."

The director general of South Africa's foreign office, Brand Fourie, spoke on the second day of a special Security Council session on the Pretoria-controlled territory of South-west Africa, or Namibia. African nations that are demanding sanctions against South Africa walked out when its representative rose to speak.

Fourie, in reacting strongly to the council's refusal yesterday to hear the South Africa-backed Democratic Turnhalle Alliance, nevertheless was careful not to rule out an "internationally recognized solution in the territory." Nor did he reject a U.N. role in supervising elections in Namibia.

The South African official did insist that any negotiating process provide long-term assurances of minority rights in the territory and equal treatment for the Democratic Turnhalle Alliance.

The council voted 9 to 6 yesterday against a hearing for the party's leader, Peter T. Calangula, while unanimously granting the floor to representatives of the Soviet-backed guerrilla group that has been waging a military struggle aginst South African forces.

This enabled Fourie to make the point today that the council "is no different from any other U.N. organ in its bias in favor of SWAPO," the Southwest Africa People's Organization.

A meeting in Geneva to negotiate the final terms of independence deadlocked in January when South Africa maintained that the United Nations could not prove its impartiality in the proposed election process. The U.S. government has taken the initiative in seeking independence for the white-dominated but majority black territory. Joining the United States in the negative vote yesterday were Britain, France, Spain, Ireland and Japan.

The South African official also warned that this government "would not take sanctions lying down but would exercise all her options and react appropriately to safeguard her own interests."

Sanctions against South Africa, he said, "would in effect amount to sanction against the countries of southern Africa, whose economies are so closely intelinked."

The action is expected to complicate U.S. proposals now being discussed in London of State-designate Chester Crocker with Britain, France, West Germany and Canada on ways to move quickly to implement the U.N. plans.

The African nations, which convened a council session more in the hope of generating international pressure on South Africa than in the expectation that sanctions would be approved, have also been cautious in their statements in these first two days of debate.

But the aura of moderation was typified by the statement from Senegal's foreign minister, Mustapha Niasse, who said that Africa "prefers a negotiated settlement rather than confrontation," and who urged the West to reassert its pressure on Pretoria to accelerate the independence of Namibia. It rules the territory under an old League of Nations mandate that the U.N. General Assembly has canceled.

Western diplomats suggested today that the Africans might suspend the council debate for a month or two after the speeches are made and sanctions resolutions are introduced, to provide time for a new approach that might break the logjam in the independence talks.

But most Africans have not been responsive either to a U.S. proposal that a Namibian constitution be drafted before elections or to a French plan for an all-parties meeting to spell out and guarantee minority rights in advance of the voting.

The Africans say they are determined to press on to a vote on sanctions, swallow the anticipated vetoes by the United States, Britain and perhaps France, and then convene a special emergency session of the General Assembly.

The sanctions would pass easily in that body since there is no veto power but neither are assembly decisions legally binding on governments.

The measures the Africans have drafted include a reiteration of the existing U.N. embargo on arms sales to South Africa, a specific ban on oil shipments, and on omnibus embargo on all trade and travel save for emergency food and medical supplies.

Washington Post correspondent Caryle Murphy reported from Johannesburg:

South African Foreign Minister Pik Botha called the refusal of the Security Council to hear the Namibian group a "provocative" act.

South African officials prefer a transition supervised by an international commission comprised of representatives of the majoy Western allies and nearby black-ruled African states.

For some months now South Africa has complained about U.N. bias against the Turnhalle Alliance and favortism toward SWAPO, which the General Assembly has designated "the sole and authentic representative of the Namibian people."

Partly to allay these allegations, U.N. officials accepted the presence of alliance representatives in the official South African delegation to the U.N.-sponsored conference in Geneva last February that failed when South Africa declined to sign a ceasefire with SWAPO.