HARARE, ZIMBABWE -- The lobby of the Sheraton Hotel in this Zimbabwean capital was thick with emotion on the opening night of an international conference on apartheid last week, as busloads of mostly black delegates began arriving from the airport after flights from Johannesburg.

Exiled South Africans anxiously searched the faces of the visitors and then cried with joy as they fell into the arms of friends from whom they had been separated for years.

Joe Slovo, the white national executive committee member of the outlawed African National Congress, was surrounded by excited delegates, many of whom regard Slovo, who fled South Africa in 1963, as a father figure of the struggle against apartheid.

For four days, Slovo, ANC President Oliver Tambo and senior executive committee member Thabo Mbeki met nearly nonstop with the 200 visiting delegates, discussing the strategy for forcing a transfer of power in South Africa from the 5 million whites to the 23 million blacks.

Although the stated purpose of the conference was to discuss the detention and alleged torture of children in South Africa, it provided an opportunity for the biggest gathering ever of top ANC leaders and other exiled antiapartheid campaigners and black nationalists who still live inside the country.

The meeting illustrated the importance the ANC attaches to its network of continuous contact between black activists in South Africa and those living abroad.

The network functions largely uninterrupted despite constant efforts by South African security police to disrupt it with methods that include surveillance, detention and the seizure of passports of people who are in frequent contact with ANC headquarters in Lusaka, Zambia.

"This conference has been extremely important, not only to get out information about the {detained} children, but for maintaining contact between those inside and outside," Slovo said.

Mbeki said the conference was important because most of the ANC leadership's contact with the inside normally is with senior figures of big organizations, such as the United Democratic Front, a coalition of 700 antiapartheid groups, and the Congress of South African Trade Unions, when they travel abroad.

"This was unusual because it involved a lot of people at the grassroots level. For most of them, it was the first time they had seen us," said Mbeki, whose father, Goven, is serving a life sentence in South Africa for treason.

During the conference, it was disclosed that since July the ANC had rebuffed three attempts by emissaries of the South African government to set up secret meetings between an unidentified Cabinet minister and the banned organization. When the conference ended, the South African delegates met with Tambo.

The meeting was closed to reporters, but two delegates who attended said Tambo, who earlier in a news conference had confirmed the South African overtures, said the ANC was holding to its position that it would not talk with Pretoria until conditions were met, including the release of imprisoned ANC leader Nelson Mandela and other political prisoners and the dismantling of the apartheid system of racial separation.

Tambo, according to one source, also addressed the controversial issue of "necklacing," the grisly slaying ritual in South Africa's black townships in which a gasoline-filled tire is placed around the neck of an accused collaborator and ignited.

According to one delegate, Tambo said press attention to "necklacing" had harmed the ANC's image and asked delegates to urge black militants not to use "that method."

Another delegate said Tambo simply reiterated that the ANC, while not explicitly condemning the practice, did not approve of it. That source said Tambo also urged the delegates to try to defuse fighting between such rival groups as the United Democratic Front and the black consciousness Azanian People's Organization.

Delegates also said Tambo stressed the importance of avoiding racial polarization in a postapartheid South Africa and urged ANC supporters to continue to try to establish a dialogue with liberal whites.

On the question of violence, Tambo is said to have told the delegates that in the case of Zimbabwe, the armed struggle did not end until negotiations between whites and blacks began. He suggested the same should hold true for South Africa.

ANC sources said the session with Tambo was important to the delegates because they will be able to report back authoritatively to their communities on the ANC leadership's current thinking on issues.

Since the leadership cannot visit South Africa, such meetings are one of the few ways that the ANC can get its message home, officials said.

Asked whether the South African government might not try to curtail such contacts by restricting the movements of antiapartheid activists, an ANC source said the danger exists, but at a cost to Pretoria.

"They have a problem. They have to project an image of being reasonable and seeking a dialogue," said the ANC source.