JOHANNESBURG, JULY 27 -- President Frederik W. de Klerk has asked the African National Congress to exclude the South African Communist Party's general secretary, Joe Slovo, from the next round of the ANC-government talks Aug. 6, following government allegations of Communist involvement in preparations for an armed insurrection.

De Klerk's request, according to local press reports today and confirmed by an ANC official, was made during a two-hour emergency meeting Thursday night between de Klerk and the ANC's deputy president, Nelson Mandela, during which the two sought to head off a crisis over preliminary peace negotiations.

ANC spokesman Pallo Jordan told a press conference here that the organization's National Executive Committee will hold a special session over the weekend to discuss de Klerk's "preference" for the exclusion of Slovo from the ANC's five-man delegation to the Aug. 6 talks.

"Our deputy president could not accept or reject Mr. de Klerk's preference as Mr. Slovo was not appointed by Mr. Mandela but by the NEC {National Executive Committee}," Jordan said.

The National Executive Committee will convey its response in time for Mandela's next meeting with de Klerk Aug. 1, Jordan said.

Jordan reiterated the ANC's position that the government's allegations of a "communist plot" should not be allowed to disrupt the start of constitutional talks to end apartheid and white-minority rule. Both Mandela and Communist officials have vehemently denied that there are any plans to launch an uprising.

According to local press reports today, documents seized by the police allegedly show that Slovo told an assembly of Communist Party members outside Durban that the party need not consider itself bound by the ANC-government agreement on a "suspension of hostilities."

The government and the ANC-Communist delegation are expected at their Aug. 6 meeting to agree on a plan that would involve the release of most political prisoners and the return of exiles in exchange for an ANC pledge to "suspend," but not end, its low-grade armed struggle.

The government has taken Slovo's alleged comments as an indication that the Communist Party is acting in bad faith and cannot be trusted as a partner in the peace process, according to local press reports.

The Johannesburg Star reported that the government was pressing Mandela to accept the possibility that legal action might be taken against Slovo and other senior Communist members in the ANC.

Local analysts said de Klerk attempted to exclude Slovo from the African nationalist delegation before the first ANC-government meeting May 3-4 and that the government appears to be in the midst of a campaign to discredit the Communist Party and get the ANC to sever its close ties to the organization.

In recent weeks, police reportedly have uncovered stockpiles of arms and explosives as well as computer files in the homes of suspected Communist Party and ANC members, which the government claim is evidence of Communist-led preparations to stage an uprising if political negotiations break down.

In addition, police reportedly have arrested from seven to 12 people allegedly involved in the plot. Among those seized was Mac Maharaj, a Communist Party and ANC executive committee member, who has played a large role in organizing the ANC's underground military operation.

Over the past three days, Communist Party and ANC officials have argued in favor of at least some preparations for an armed struggle, if not a full-scale insurrection. Party officials have openly admitted that the two closely allied organizations are continuing to infiltrate guerrillas and arms into the country. The ANC's military wing, Spear of the Nation, is also being built up as an "insurance policy," an ANC-Communist Party senior official said Thursday.

According to Ronnie Kasrils, the former head of the ANC's military intelligence unit, there might have been a "discussion document" concerning a possible uprising. But, he said, "There's been no decision, no blueprint on insurrection."