By Andrew Green
JUBA (Reuters) - South Sudan's former Vice President Riek Machar said on Friday he planned to become the frontrunner for the ruling SPLM party in elections in 2015, throwing down the gauntlet to President Salva Kiir who dismissed him three days ago.
Kiir touched off a power struggle in the African oil-producing country by firing Machar and his cabinet and placing under investigation his top Sudan negotiator, Pagan Amum, in the biggest shakeup since the South gained independence in 2011.
Analysts say the struggle risks undermining a consensus among tribes and militias leaders holding together the unruly country at a time of heightened tensions with Sudan over crucial oil flows.
In his first comments since his dismissal, Machar said he planned to head the Sudan People's Liberation Movement (SPLM), which led the country to secession from Khartoum after fighting one of Africa's longest civil wars.
"I have told my colleagues in the politburo that come the next elections in 2015, I would contest those elections," Machar told reporters in the capital Juba.
He said he wanted to run for the sake of democracy. "I believe that this country must go democratic. If it is going to be united, it cannot tolerate one man's rule. It cannot tolerate dictatorship. It cannot tolerate tyranny."
His spokesman James Gatdet Dak clarified Machar would run for the SPLM chairmanship before the vote to pave his way to the presidency of the one-party state.
Machar said he accepted his sacking as vice president but accused Kiir of creating a political vacuum for not immediately appointing a new cabinet.
"We now have a vacuum and this has created apprehension," added Machar, who said he was "telling people to remain calm".
A government officials said Kiir was still consulting the party on a new cabinet probably to be formed by early next week.
Stability in South Sudan is key for crude producers from China, India and Malaysia operating in the country and east African neighbors Ethiopia, Kenya and Uganda which got swamped with refugees during the civil war.
Kiir has headed the south since civil war hero John Garang died in a helicopter crash in 2005, shortly after the SPLM had signed a peace deal with Khartoum.
A no-nonsense army man, Kiir commands great respect across the country the size of France for his role in uniting the often squabbling tribes and militias which make up the elite.
But Kiir has been facing dissent from inside his party, normal people and donors failing to deliver on a "peace" development dividend in the war-torn country. Some $4 billion in public money has been stolen, according to Kiir, roughly a third what Sudan made in oil revenue since 2005.
Machar, best known for his marriage to the late glamorous British aid worker Emma McCune, is one of the most controversial characters in South Sudan - he sided with Khartoum during the civil war, which led to the split of the rebel and southerners killing each others. Critics blame him for a inter-tribal massacre of thousands in Bor in 1991.
But Machar, also known for his broad smile, is respected among his Nuer, one of the biggest tribes after Kiir's dominant Dinka. He is well-spoken and holds a PhD degree from the U.S. university of Bradford, a contrast to Kiir who spent much of his life in the bush.
South Sudanese political analyst Andrea Mabior said Kiir would probably get the 2015 ticket but Machar's plan would create division. "It is very obvious the party is going to split," he said, although added that he expected no violence.
Apart from Machar, Amum has also indicated he could challenge Kiir as SPLM head.
Machar attacked Kiir for banning Amum for travelling abroad, and also recently removing two state governors. "I also think we have constitutional crisis. I still maintain that the president has no right to dismiss elected governors," he said.
The domestic showdown comes at a time when state coffers are almost empty after a 16-month oil shutdown and a threat from Sudan to block again oil exports from the landlocked country. Oil is the lifeline for both countries.
(Reporting by Andrew Green; Writing by Ulf Laessing)