Black African nations today sharply criticized "loopholes" in the Carter administration's proposal for a mandatory U.N. arms embargo against South Africa and termed the Western desire to make the resolution renewable after six months "totally unacceptable."

Following meetings among themselvies and with U.S. and Western delegates, African envoys said that unless a compromise is reached by Monday, they will press for a vote on their own resolutions that call for economic sanctions against South Africa as well as an arms ban.

The draft Western resolution, which was approved late yesterday by the United States, Britain, France, Canada and West Germany, would direct all U.N. members to cease any provision of arms to South Africa including the sale and transfer of arms, ammunition of all types, military vehicles, and equipment and material for the manufacture of arms and ammunition, paramilitary police equipment, and spare parts."

African delegates were critical of the fact, however, that the Western resolution made no mention of halting all nuclear cooperation with Pretoria, and even more important, that it failed to bar the granting of licenses to South Africa for production of such military items as armored cars or jet fighters.

"What's the point if we have an arms embargo and the South Africans continues to make all the Mirages they need under French license," asked Tanzanian Ambassador Salim A. Salim, a leader of the African group.

"If you are going to have a mandatory arms embargo, it is important to plug every type of loophole, "he declared. "There's no point of telling ourselves we are making a mandatory arms embargo, and then the South Africans continue to get arms one way or another."

Black African delegates declared that they would not agree to support an embargo that expired at any fixed date in the future.

The timing factor is completely unacceptable," declared Salim. "We are saying: "This is a regime that cannot be supplied with arms - today, tomorrow, the day after tomorrow, next year or the year after next."

The United States and other Western nations appeared reluctant to compromise on this point, however, arguing that a permanent embargo would make the ban simply punitive, and remove any incentive for South Africa to change its policies.

Emerging from a meeting with African leaders, U.S. ambassador Andrew Young said the United States remained opposed to a permanent ban because any effort to remove it later would almost certainly be vetoed by the Soviet Union or China.

"If South Africa were to let people out of jail and make some effort to change the situation - and they could after the election - then we would be in a position of not being able to vote to change the situation without the Russian and Chinese approval," Young said.

Young said it was important that the embargo be imposed for a fixed term to enable the United States to "keep some influence over the situation" in South Africa.

The South Africa election, scheduled for Nov. 30, is expected to show great support for the white-minority ruling Afrikaner party.

Black African nations also expressed concern over the failure of the Western resolution to specifically state that the arms embargo was being imposed under Chapter 7 of the U.N. Charter, which authoritizes measures against nations that constitute "a threat to the maintenance of international peace and security."

The Western draft omits any direct reference to Chapter 7, but it does declare "that the aquisition by South Africa of arms and related materials in the current situation brought about by the repressive policies of South Africa constitutes a threat to the maintenance of international peace and security."

U.S. and other Western delegates argue that the omission of any direct reference to Chapter 7 is inconsequential, since the language is the same.

"We can't accept that," said Salim. "We are saying that the situation in South Africa is a threat to international peace and security. The West is saying that the supply of arms is a threat to the international peace and security. It's two different concepts."

Privately, French and British officials concede this point. They express concern that if South Africa is specifically cited under Chapter 7 in an arms embargo resolution, that the African states will be back, quickly seeking economic sanctions by arguing that the nature of the Pretoria regime had already been established.

The four African resolutions currently before the Security Council go far beyond the Western draft proposal.

In addition to calling for a total arms embargo, the African resolutions cite Pretoria as a "grave threat to international peace and security" under Chapter 7, call for a band on investment and trade, and demand that the Pretoria regime immediately abolish its sytem of apartheid.

These resolutions, if pressed to a vote, would certainly meet the fate of similar resolutions calling for sanctions against South Africa in the past, which have been vetoed by the United States, France, and Britain.

"I don't think one can talk about vetoes at this point," said Salim. Western and black African nations plans to continue their intensive consultations over the weekend, and both sides remain hopeful of reaching a compromise.

"We want a mandatory arms embargo with no time limit, and we want the South Africans to be specifically cited under Chapter 7," declared Salim. "If this can be accepted, fine. Otherwise, we have our four resolutions and we will go on."