AT NOON last Sunday, as hundreds of mourners waited to fly out of Sudan’s Juba airport after the funeral of the country’s vice-president, John Garang, a sleek corporate jet touched down and taxied towards the tiny terminal.

Two men wearing suits and dark glasses emerged from the aircraft and slipped quickly through the arrivals hall into a dark green SUV. Their car pulled up at a house where Salva Kiir, the newly appointed leader of south Sudan, was staying.

Kiir had taken calls from world rulers all week and played host to African leaders at the funeral the day before. He had just finished a meeting with Jan Pronk, the United Nations special envoy for Sudan.

Now it was the turn of two directors from an AIM-listed company.

“We wanted to offer our condolences and to wish Mr Kiir the best,” says Andrew Groves, co-founder of White Nile, the oil company whose gamble on south Sudan has turned it into one of Britain’s most hyped shares since the dot-com era.

“To reinforce our relationship,” adds Phil Edmonds, the 54-year-old former England cricketer and chairman of the company. “White Nile is the only company I know of that came to here to pay its respects.”

But then White Nile is no ordinary company. The Sudan People’s Liberation Movement (SPLM) — the rebel group that waged a 21-year civil war against the Muslim North and will soon form the government of south Sudan — owns 50 per cent of its shares.

In return, the SPLM awarded White Nile a 60 per cent stake in the lucrative Block Ba oil concession in south Sudan, thought to contain up to five billion barrels of oil. The highly controversial move — the French oil giant Total already claims ownership of the oilfield — sent White Nile’s shares soaring from 10p to 138½p in the days after their market debut in early February.

By the end of July, the shares were still riding high at 101p.

But the death of Garang, who was seen as the glue in a fragile north-south peace deal signed in January, and the fierce rioting that followed spooked White Nile’s investors. The stock slumped 12 per cent, wiping almost £40 million off the firm’s market capitalisation, and the critics who had bet against Edmonds and Groves, both of whom have made paper fortunes from their personal holdings, rubbed their hands in glee.

But by the time the two men reached Juba on Sunday, the situation in Sudan was calm, helped in part by the swift appointment of Kiir to head the SPLM. For White Nile, the appointment was good news. Both Edmonds and Groves had met Kiir several times. Indeed, Groves was in a meeting with him when John Garang began the journey home that ended with his helicopter crashing into a mountain on July 31.

“We are close to Salva Kiir, and to the SPLM as a whole,” says Groves, a fresh-faced 37-year-old South African, on the flight back to Nairobi after the meeting with Kiir.

The relationship will need to stay tight, for there remain huge challenges for White Nile to overcome before any oil is pumped from Block Ba, not least from Total.

The French oil company bought the Block Ba concession from the Khartoum Government in 1980, but never developed it as war broke out in south Sudan three years later. Under the peace agreement signed by the SPLM and the Government in January, both parties agreed that any oil deals already struck would stand. Unbeknown to Khartoum, however, the SPLM had awarded Block Ba to its own Nile Petroleum Company in August 2004. When the peace deal was signed, the SPLM insisted that this contract must stand, and promptly transferred 60 per cent of the Block Ba oilfield to White Nile.

Total, which renewed its licence over the field with the Khartoum Government in December, was furious. “We get angry letters from their lawyers every week saying we are interfering in ‘their block’,” says Groves. “It’s not their block. If it is, the SPLM may as well go to Paris to claim the Eiffel Tower.”

Edmonds chuckles, for he is in a good mood, having just heard of England’s two-run Ashes Test win against Australia. But then he puts on a serious face.

“We are bemused by the arrogant, neo-colonial attitude of Total,” he says. “If they want to get heavy, then they should try to get heavy with the Government of south Sudan, and see where that takes them.”

It is not difficult to see why the SPLM is keen for the White Nile deal to succeed. Under a conventional deal with a major oil company, it could expect an upfront bonus and a share of future revenues. But with the White Nile agreement, the SPLM’s stake in the company is already worth £130 million, even though oil will not be pumped for at least five years.

“Why should the south Sudanese take the crumbs of the table that Total will offer them?” says Groves. “What we have said is: ‘This is your oil and you should exploit it. We will give you access to world capital markets and the mechanisms to extract the oil.’ ”

Total is still convinced that it has a valid licence to explore the Block Ba concession. “We have asked Queen’s Counsel in London to study the case on our behalf with a view to taking legal action,” a spokesman says.

There are also questions about whether Khartoum will try to block the White Nile deal. When it was announced, Sudan’s Oil Minister claimed the agreement was illegal, although in recent months little more has been heard.

Despite all the legal and political risks that make White Nile a risky bet, the company has already started a $16 million exploration project on the concession.

“We like to think that we are reasonably good at judging risk,” says Edmonds with a grin.

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