Former African National Congress national chairperson Mosiuoa Lekota is a "shameless opportunist", the Gauteng branch of the Umkhonto WeSizwe Military Veteran's Association said on Monday.

"We certainly cannot allow opportunists to derail our revolution," the branch said in a statement.

"We must not allow postponement of delivery of the Freedom Charter on account of shameless opportunists like Lekota and his brigands."

The association said a genuine member of the ANC with the interests of ordinary people at heart would not dare to stand aside and oppose the decisions taken at the party's conference in Polokwane.

"But alas! Words fail; ordinary terms are inadequate to describe the charade led by Terror Lekota and Mluleki George."

The association said during apartheid struggles, its veterans were taught by the ANC about the values of democratic centralism.

"This principle allows us to differ as much we like on any and all issues under discussion.

"Equally importantly, the ANC taught us that, having finally agreed on a line of march, none should stand aside. We all should fall in line with the popular decision.

"Without this discipline, no organisation can hope to exist and deliver on its core mandate," said the Gauteng military veterans.

The association said the same kind of procedure was followed with decisions taken at Polokwane.

"The dangers of political careerism at the expense of our people's interests must be exposed," said the MKMVA.

"We must not allow [ourselves] to be disarmed by losers."

Earlier on Monday, ANC treasurer general Mathews Phosa and Lekota, the former minister of defence, held a meeting to discuss concerns Lekota raised in an open letter to the ANC leadership two weeks ago.

Lekota is speculated to announce the launch of a new political party soon.

Last week Lekota announced he was serving "divorce papers" on the ANC, but Phosa responded by saying the "marriage" could still be saved.

Lekota's letter and announcement last week were seen as further indication of an impending split in the ruling party, on the heels of its recall of former president Thabo Mbeki and a swathe of resignations, including those of Cabinet members and Gauteng premier Mbhazima Shilowa.

Transport Minister Jeff Radebe, a member of the NEC, responded in his own open letter, saying: "Put bluntly, you and those who share your views are giving notice to leave the ANC."

Lekota had claimed that ANC members who expressed views contrary to popular opinion were later "hounded out" and "purged" from organisational and state structures.

Newspapers on Monday suggested that Shilowa was set to join Lekota in a new party.

Sapa