Russian specialists planned to influence South Africa’s general election in order to strengthen the ruling African National Congress party (ANC), documents seen by the Guardian and local media in South Africa suggest.

The documents were apparently prepared by an organisation linked to Yevgeny Prigozhin, a St Petersburg businessman who is close to Vladimir Putin. They promise a campaign “to support the ruling ANC ahead of elections” and to counteract and “discredit” the pro-western Democratic Alliance party. It is unclear whether the plan was executed. The plan was first reported by the Daily Maverick newspaper.

Voting booths opened on Wednesday in South Africa’s sixth general election since the first free polls in the country in 1994. The ANC has held power ever since but faces widespread discontent among voters angered by a series of major corruption scandals, power cuts, inflation and unemployment.

South Africa goes to polls as ANC hopes to reverse slide in support Read more

There is little doubt that the ANC will obtain a majority in parliament and that the incumbent president, Cyril Ramaphosa, will get a new mandate. However, supporters say he needs to show he has reversed a steady decline in the ANC’s popularity if he is to implement an ambitious reform agenda that has stalled since he took power last year.

The plan to interfere in South Africa’s election was coordinated by a Russian political technologist, Peter Bychkov, who works for Prigozhin, according to the documents. The disinformation campaign was plotted by a Russian-owned NGO, the Association for Free Research and International Cooperation (Afric), under the guise of research.

In February, according to the documents, Bychkov dispatched a small team of political analysts from St Petersburg to South Africa. They were based within Afric and another research outfit, the International Anticrisis Center (IAC). This appears to be the first time the Prigozhin network has been active in South Africa, but there is no evidence it had any effect, the paper said.

The documents were obtained by the Dossier Center, an investigative unit based in London and funded by the Russian businessman and Kremlin critic Mikhail Khodorkovsky.

Moscow’s goal was to tarnish the reputation of the leaders of the Democratic Alliance (DA) and the Economic Freedom Fighters (EFF), a far-left party headed by a former ANC official, the documents suggest. Tactics include “public rhetoric”, “generating and disseminating video content”, “coordinating with a loyal pool of journalists” and “producing pro-ANC videos”.

The documents include several pages of analysis that suggest the ANC will struggle to poll above 50% and that the EFF is likely to come second.

This runs against most experts’ projections, which place the ruling party on between 55% and 60%, the DA on about 20% and the EFF on 15% at most.

In recent years, Russia has sought to play an increasing role in Africa and to boost its military and political presence on the continent. In October, Putin will host an Africa-Russia summit in the resort of Sochi. The Kremlin’s apparent strategy is to support incumbent presidents and to work against “pro-western” parties and reform movements.

According to the US special counsel Robert Mueller, who investigated Russia’s attempts to influence the 2016 US election, Prigozhin runs the notorious troll factory in St Petersburg – the Internet Research Agency (IRA) – and was responsible for an extensive social media operation in 2016 to mobilise support for Donald Trump and to disparage Hillary Clinton. Afric and the IAC are IRA offshoots, according to the documents.

Prigozhin is linked to the Wagner Group, a paramilitary organisation that has been active in several African states, including the Central African Republic. His political operatives popped up last year in Sudan and tried unsuccessfully to keep President Bashir in power. They also travelled to Madagascar ahead of elections there last November.

The South Africa operation was smaller and more lacklustre than Moscow’s recent extensive effort in Sudan. Nevertheless it appears to be an example of the Kremlin’s ambition, opportunism, and desire to stop dead in its tracks any “pro-western” shift, whether in Africa or elsewhere.

Bychkov denied any knowledge of the operation, the Daily Maverick reported, saying: “Yes, listen, well, if someone somewhere wrote something, it’s a fantasy. I have never dealt with all this African politics. I am in St Petersburg and doing other things.”

The ANC has had good relations with Moscow since the days of its long and bitter battle against the racist apartheid regime.