Newly-sworn-in Deputy President David "DD" Mabuza has dismissed talk about him being linked to criminal dealings as a smear campaign that started as far back as 2009.

Mabuza was announced as President Cyril Ramaphosa's deputy on Monday night, following a Cabinet reshuffle. He and other newly-appointed ministers were sworn in on Tuesday.

Mabuza, who was the premier of Mpumalanga since 2009, has been accused of running the province as his own personal fiefdom, including getting rid of political opponents in the province.

But, after his swearing in as the new deputy president, he dismissed allegations that he was involved in corruption and other dealings as a smear campaign.

"The campaign started in 2009 the moment I became premier, because people did not expect a village boy becoming premier. They will not accept it," he said.

"Since 2009, and now [it] is 2018, nine years later, they are still talking about this thing and now I am deputy president. And they will probably talk about these things until I die."

Mabuza encouraged anyone who has seen him or any other citizen commit a crime to report it to the authorities.

"No one wants to step forward and say: 'I’ve seen DD Mabuza commit this and this and this. I am prepared to go and testify in court'," he said.

"A responsible citizen, really you [are] trying, helping the country to fight crime, fight corruption. No, no one will blame you for that," he added.

Mabuza, who was a supporter of former president Jacob Zuma, has referred to himself as "The Cat" for his many political lives. Despite allegations levelled against him, he maintains it is nothing but a smear campaign.

"An allegation of corruption, of crime, of anything, we're a Constitutional democracy, we have got these institutions to report to the relevant people. But if you choose not to report it, but talk about it, that means your intention is not a good intention. So you can read between the lines that probably those people that are talking about those allegations they realise a certain potential in me," Mabuza said.

"But if you talk, and I realise you are a political opponent, or you are within the ANC, because even within the same party there is a push and push and push," he added.

Mabuza told reporters that he wanted "to help our media" to avoid more rumours.

"I want to help our media, it is always important to write about something that has got a base. Don't write about something that is baseless… you can't write about rumours."

"We are taking a wrong culture, a culture of rumours… Let’s not abuse it. Because I hate someone, I report, I say false things. No, just to advance my own ambitious. That won’t help our country," he added.

Mabuza said he would encourage any person to report any form of crime, whether it was corruption, or women and child abuse.