South African President Jacob Zuma has addressed calls by his ruling African National Congress (ANC) party for his resignation as "unfair."

"There's nothing I've done wrong," Zuma said, speaking on state television Wednesday, adding that he thought that the party was being plunged into a crisis its members would regret. "I'm being victimized," he said.

Zuma is due to make a statement later on Wednesday.

The ANC said earlier Wednesday that it would back a fast-tracked no-confidence motion against the president in parliament Thursday, raised by an opposition party.

This was the most recent in a series of blows that ANC has dealt to Zuma in an attempt to shake itself free from his scandal-laden government. The ANC called for his removal from office on Tuesday, although the party did not specify a time frame for him to leave.

Markets reacted swiftly to the news, with the South African rand hitting a 2.5-year high against the U.S. dollar on Wednesday. The U.S. currency sank in relation to the rand by 2 percent at approximately 11:40 a.m. ET Wednesday. Johannesburg's Top 40 index was trading 0.3 percent higher.

Zuma was replaced by Ramaphosa as head of the ANC in December. Ramaphosa is a former trade union leader-turned-politician and one of South Africa's richest men.