South Africa has generally had strong relations with Zimbabwe, but some say a last week's hiccup over criticism of election preparations reveals the diplomatic fine line the southern African nations walk.
Last week, Lindiwe Zulu, a top international advisor to South African President Jacob Zuma, voiced concern that Zimbabwe was not well-prepared for the July 31 election, saying Zuma had spoken to Zimbabwe's President Robert Mugabe by phone about the matter.
President Mugabe responded quickly, calling Zulu a "stupid and idiotic street woman" who should be restricted from speaking about the vote.
Zuma's office then released a statement saying it regretted the unauthorized statements and denying there had been any such phone call in which Zuma criticized election preparations. Clayton Monyela, South Africa's head of public diplomacy, said only Zuma would speak on matters relating to his responsibilities as a facilitator bilateral mediation.
"There was a concern obviously raised by the president of Zimbabwe with regards to who speaks on behalf of the mediation facilitation team," said Monyela. "So that matter has been dealt with. ... It's an exaggeration to say [it] translated into tensions. We've got good, healthy, cordial, friendly, historical relations with the government of Zimbabwe as a country, on a bilateral level."
But experts suggest the relationship has its own share of complexities.
Gilbert Khadiagala, who teaches at the University of Witwaterand's Department of International Relations, said Zuma's predecessor, Thabo Mbeki, had used what many called a quiet diplomacy with Mugabe, rarely criticizing him in public, though sometimes arm twisting in private.
Unlike Mbeki, he added, Zuma has been harsher on Mugabe. "I'm saying the recent incidents around Lindiwe Zulu show that he's departing from that line of toughness," Khadiagala said. "When you lose that toughness, you undercut all these efforts by the regional actors. So I think Zuma has been doing very well until very recently, [and] I think he's now beginning to look like he's kowtowing to Mugabe."
Caving to Mugabe's demands on Zulu, Khadiagala says, indicates Zuma's unwillingness to upset relations.
"I can imagine that Zuma doesn't really want to rock the boat, because he's the leader of the Southern Africa Development Community (SADC) group on Zimbabwe," Khadiagala said. "And they are interested in a soft landing during these elections. I don't think they want to antagonize Mugabe."
But he also says that position weakens South Africa and the SADC, which is helping to facilitate and oversee the elections.
"When Lindiwe Zulu is rebuked by Zuma it looks like South Africa is actually looking very weak," he said. "And that weakness is translated into a very weak SADC, that has been weakening every day. My point is that SADC is becoming even weaker when it comes to Zimbabwe and that's not a very good sign."
There is also a historical pressure for mutual support, as the parties of Presidents Zuma and Mugabe are linked through liberation movements.
"The historical links between the liberation movement parties — ZANU-PF [and] ANC — is very much a cozy relationship," he said. "There's a lot of pressure here in South Africa within the ANC not to criticize Zimbabwe, because they look at Mugabe as the freedom fighter."
That pressure, he said, makes behind-the-scenes diplomacy an easier route.
"These are single party mentalities that have been historically forged over the years," he said. "It's essentially a continuation of the quiet diplomacy under Mbeki, that South Africa should not be seen to be too harsh on Mugabe, because maybe if you talk to him quietly, maybe he's going to change."
Khadiagala is predicting a win for the 89-year-old Mugabe.