Plans by the United States to establish a new Africa Command (Africom) on the continent next year are fraying relations with some African countries, including South Africa.
Some analysts believe that South Africa is leading moves to prevent an Africom presence in Southern Africa and others believe wider moves are afoot to keep it out of the whole continent.
The tensions broke the surface this week when Eric Bost, the outspoken US ambassador to South Africa, complained that Mosiuoa Lekota, the defence minister, was not responding to embassy requests to meet General Kip Ward, the recently nominated first commander of Africom.
Ward is in South Africa to take part in a high-level seminar on Africom being conducted by the Johannesburg-based Brenthurst Foundation.
He was hoping to meet Lekota while in the country but this now seems unlikely.
"We have, over the course of the past two months, endeavoured to secure a meeting between General Ward and Minister Lekota in a variety of ways, both formal and informal," Bost said in an interview. "Unfortunately, to my knowledge, we have not had any response to these efforts.
"This fact is made more unfortunate in light of the recent announcement of General Ward's nomination to head the new Africa Command."
Lekota's spokesperson, Sam Mkhwanazi, said that the issue of the meeting had been dealt with when Bost and Jendayi Frazer, the US assistant secretary of state for Africa, met Lekota in Cape Town last month.
But US officials said that, although Bost and Frazer had again asked Lekota to meet Ward, no meeting had been arranged.
African suspicions about US intentions for Africom were evident this week when Theresa Whelan, the US deputy assistant defence secretary, addressed the Centre for International Policy Studies at the University of Pretoria. Many African governments suspect that the real purpose of Africom is to facilitate the US war against international terrorism in Africa.
Whelan insisted, though, that its main aim was to support and increase the capacity of Africa's planned African Standby Force for peacekeeping.
Helping Africans improve security on their continent would indirectly serve US national interests, making it less likely that the continent could be used as a launching pad for terror against the US.
She stressed that no combat troops would be stationed at Africom, but only headquarters staff and officials of other US departments, such as diplomats and aid workers, to help its development function.
The US had decided to station Africom in several different countries to allay African concerns that a single, concentrated US presence would be overwhelming, Whelan said.
Bost said the US had not yet decided in which countries it would base Africom.
Though the US has said before that it would like to divide Africom among the five regions of Africa to improve co-operation with the continent's organisations, it now seems unlikely to have a presence in Southern Africa.
Whelan said that other regional organisations were happy to work with Africom, but not the Southern African Development Community (SADC).
That was fine, she said. The US would sever military-to-military relations with the SADC but continue bilateral relations with whichever SADC member countries wanted them.
Dr Jakkie Cilliers, the head of the Institute for Security Studies in Pretoria, said he believed that South Africa might be leading the SADC move against Africom, "not so much because we don't like the US, but because we want to be the big boys".
Whelan insisted that Africom was being created mainly to rationalise US international military command structures, as different African countries now fell under three different US military commands.
Abdullah Alzubedi, Libya's ambassador to South Africa, asked Whelan how the US could divide the world up into its own military commands. Wasn't that for the United Nations to do? he asked. And if China, say, decided also to create an Africa Command, would that not cause conflict?
Whelan reiterated that the US' regional military commands, such as Africom, were organisational divisions within the US military bureaucracy and did not imply any US control over those regions.
Cilliers said that, whatever the US claimed, he was sure that the main purpose of Africom was to advance US military interests, such as the fight against terrorism.
But, since the US would establish Africom anyway, he advised African governments to "limit the damage" by co-operating with the US and steering Africom towards greater support for the African Standby Force.