The Rev. Ndabaningi Sithole, one of three black leaders who have joined Rhodesian Prime Minister Ian Smith in the biracial transitional government there, yesterday defended the weekend raid on 10 gurella bases in neighboring Mozambique by the white-led Rhodesian defense force.

"Sometimes we have to do things that we don't like to do normally," Sithole said in an interview on Rhodesian television, referring to the two-day air operation during which Rhodesian military forces said they "neutralized" 10 bases of Robert Mugabe's Zimbabwe African National Liberation Army.

Up to now, Sithole and his black colleague, Bishop Abel Muzorewa, who both claim the allegiance of a majority of the guerillas, have criticized such large-scale antiguerilla operations by the Rhodesian army, especially when they spilled over into neighboring black-ruled states. The black leaders also blamed white political and military authorities for not achieving a cease-fire with the guerilla armies of Mugabe and Joshua Nkomo.

Sithole's statement yesterday is an indication that as the war grows more heated, Sithole and Muzorewa can no longer expect the support of the Rhodesian army while at the same time reciminating against it.

Referring to reports on Rhodesian military authorities that guerilla groups are being sent into Rhodesia to assassinate the black leaders, Sithole said, "We must deal with them. We must protect those who believe in our leadership.

"We have started a democratic process but there are forces outside the country which would like to disrupt it. Necessity does impose on us to be vigilant. It does impose on us to defend ourselves as well as we can" said Sithole. In the past, he had claimed to enjoy the support of over 70 per cent of the guerillas.

Sithole and Smith said separately yesterday that elections for an independent government would be held before the end of the year even if a complete cease-fire was not attained, indicating that hopes are fading in government circles for a total end to the war. It is unlikely that even those in the United States and Britain, the former colonial power, who sympathize with the internal settlement could regard the elections as valid under such circumstances.

Speaking in Rhodesia's House of Assembly, Smith conceded that the cease-fire was not yet effective but added that "if it is necessary we can and will (hold elections) even under present circumstances." Sithole said he did not think it was necessary to have a complete cease-fire to hold elections based on the principle of universal suffrage.

Meanwhile, Zambian President Kenneth Kaunda, who allows Nkomo's guerilla forces to operate from his territory, condemned the weekend attack on Mozambique, in which Mozambican authorities said 12 people died and 110 were wounded.

"I have learned with indignation of yet another cowardly and unprovoked aggression against your country by the illegal Rhodesian rebel troops" Kaunda wrote to Mozambican President Samora Machel. It is the fifth time the Rhodesians have acknowledged a raid into Mozambiqque.