By Paul Simao

JOHANNESBURG, Apr 3 (Reuters) South Africa's former Deputy President Jacob Zuma today took the stand in his rape trial, suggesting the charges were part of a political plot designed to bury his hopes of becoming the next president.

Zuma accused senior officials, including Intelligence Minister Ronnie Kasrils, of being part of a secretive group working within the government and the ruling African National Congress (ANC) to thwart his political career.

Zuma, speaking in his isiZulu mother-tongue, detailed his history with the anti-apartheid struggle and links with the family of his accuser -- a 31-year-old AIDS activist who says the 63-year-old politician raped her at his Johannesburg home in November.

Zuma's appearance followed a decision last week by Johannesburg High Court Judge Willem van der Merwe not to dismiss the state's case, which Zuma's lawyers had argued lacked sufficient evidence.

Once seen as the leading candidate to succeed President Thabo Mbeki when his current term expires in 2009, Zuma was sacked last year amid a corruption scandal and was later hit with the rape charge.

Zuma, who remains deputy president of the ruling African National Congress (ANC), has repeatedly asserted that the graft charges against him are a plot by his enemies to derail his presidential hopes, fanning political tensions within the party.

He is expected to testify in the current trial that he had consensual sex with the woman but that it was not rape.

Responding to a question from lead defence lawyer Kemp J.

Kemp on whether he believed the rape charges also stemmed from a secret political agenda against him within elements of the ANC and government, Zuma replied ''yes, my lord, I am aware of that''.

He later named Kasrils, a longtime ANC stalwart, and former director of public prosecutions Bulelani Ngcuka, whose wife Phumzile Mlambo-Ngcuka succeeded Zuma as deputy president, as part of a group working against him.

The rape trial has already featured graphic testimony from his accuser, who charged that Zuma forced himself on her without using a condom despite knowing that she was HIV-positive.

Defence lawyers have sought to discredit the woman, who under South African law cannot be named, by detailing episodes of her sexual history and depicting her encounter with Zuma as one of mutual flirtation.

A guilty verdict in the non-jury trial could bring up to 15 years in jail.

Zuma today denied his accuser's description of their relationship as familial despite long-standing links between the two families forged during the liberation struggle.

''That is very wrong to say that there was a father-daughter relationship. There was never such a relationship,'' he said, adding that he had noticed an increasingly flirtatious tone to her telephone text messages prior to the November incident.

''She would add the words 'love', 'hug', 'kisses'. That was really new,'' he said.

A small crowd of Zuma supporters gathered outside the Johannesburg court house as he testified inside -- far fewer than the thousands who showed up to shout their support for him at the start of the trial.

REUTERS om ht1622