General-secretary of the National Union of Metalworkers of South Africa (Numsa) Irvin Jim has accused the leadership of the union's umbrella federation, the South African Federation of Trade Unions (Saftu) accusing its leaders of trying to influence, and even sabotage its national congress.

Jim was tabling his secretariat report before Numsa members at the union's interdicted national congress on Wednesday evening. Later that evening he was re-elected unopposed as the union's secretary-general.

Numsa held its congress despite a Labour Court interdict ordering the union to lift the suspensions of members and ensure it can hold a congress consistent with its own constitution before proceeding. Numsa's appeal against the ruling was heard on an urgent basis at the Labour Court on Wednesday.

The first Labour Court case was initiated by Numsa's second deputy president Ruth Ntlokotse, who wanted her suspension overturned. She said she was suspended to keep her from running for Numsa president at the congress. Andrew Chirwa ran for the position unopposed and was elected.

In May, Ntlokotse was elected Saftu president at the federation's congress. This means she works alongside Saftu general-secretary Zwelinzima Vavi, who has openly criticized Numsa's leadership and disagrees with Jim on whether Saftu should align itself with a political party.

Jim said the relationship between Saftu and its biggest member union, Numsa, had become so fraught that the federation was working to undermine the leadership of the union.

"We never thought that ahead of a Numsa congress, this movement that we catalysed, we would be undermined. The Labour Court is hearing our appeal tonight. The leadership of Saftu has been reckless and arrogant. When you talk about interference, they look to do as they please," said Jim.

Jim said Saftu national office bearers claimed collective unity of its affiliates but does not consult with affiliates before taking positions publicly. He slammed Saftu's leadership as arrogant and accused Ntlokotse of trying to sabotage Numsa and its congress.

"Ahead of this conference, Numsa was actively campaigning in regions to put up the leadership they wanted ahead of the Numsa congress. We were looking at Ruth in her eyes during meetings as she was planning to sabotage us," Jim said.

Ntlokose told Fin24 that she did not wish to speak on behalf of Safta as they have not met to discuss Jim's comments. Vavi could not be immediately reached for comment.

While Jim was delivering his secretariat report to the congress, the Labour Court heard arguments from the union in its appeal against the previous ruling. Labour Court Judge Graham Moshoana is expected to rule on Numsa's application for leave to appeal on Thursday morning.