SACP secretary-general Blade Nzimande has lambasted former director-general in the Presidency Reverend Frank Chikane for being on a campaign to discredit President Jacob Zuma.

Chikane - who served under former president Thabo Mbeki - has written a book about how the ANC humiliated his former boss when Mbeki was recalled in 2008.

"Reverend Frank Chikane writes a completely biased book as if we were not there when the matters he is speaking about took place. It is as if we were not there when there was a sustained offensive by his ilk against communists in our movement," Nzimande said during a Gauteng SACP conference in Benoni on Saturday.

Chikane has come under fire from several Zuma supporters, including KwaZulu-Natal Premier Zweli Mkhize.

They have described his book as biased and depicting Mbeki as a blameless victim.

"We are seeing another confluence of ideological initiates that are seeking to undermine the unity of our movement, to discredit the president [Zuma] and government."

In his address Nzimande once again lambasted those opposed to his dual role as cabinet minister and party leader.

Some Cosatu members have argued that the situation compromised Nzimande's role as SACP leader because as a minister he has to toe the government line.

Nzimande has previously argued that his inclusion in government was in line with the party's strategy of having communists in all spheres of society. He accused those questioning his position of being "anti-communists".

Nzimande also called on the Young Communist League to be present in the ANC Youth League to influence its direction.

"The YCL must politicise the ANC Youth League. You cannot be fighting for economic freedom and be against communists."