The African National Congress and Ciskei security forces accused each other Friday of terrorism, but there were signs of a thaw in ANC relations with President F.W. de Klerk.

The ANC announced Thursday it was willing to meet de Klerk to discuss ways of resolving political violence.De Klerk requested an urgent meeting following the killing of 25 protesters by police and soldiers in the nominally independent Ciskei homeland. The violence erupted as thousands of ANC supporters marched across the Ciskei border to protest its military government.

The ANC attached conditions that have blocked previous bids to revive talks, but the statement was the closest it has come to agreeing to meet de Klerk since negotiations were derailed in June.

"A meeting . . . could have some merit if it were to address the problem of violence," ANC Secretary General Cyril Ramaphosa told reporters.

To ensure success, the meeting must be preceded by "thorough preparations . . . as well as practical actions" to meet ANC demands for an end to political violence and freedom for political prisoners, he said.

De Klerk on Friday welcomed the ANC's tentative acceptance of a meeting and said it should be held immediately. The ANC's conditions are points that could be discussed at the meeting, he said.

Ramaphosa says relations with the South African government are at their "lowest ebb . . . ever" because of the Ciskei bloodshed.

The killings prompted retaliatory attacks on homes of Ciskei police and soldiers in villages around Bisho, the Ciskei capital.