Despite a year of significant changes and the largest humanitarian airlift in history, Sudan's political and military impasse continues. The war without end is still bleeding the country dry and ravishing its population. Despite government attempts to civilianise and legitimise the regime, the SPLA and the exiled opposition of the National Democratic Alliance still refuse to re-enter the political process on Khartoum's terms. Peter Moszynski reports.

A recent study by the US Committee for Refugees estimates that one in five Southern Sudanese has died as a result of the 15-year war - almost two million people, the highest death toll of any conflict in the world today.

Last year saw some of the highest malnutrition rates ever recorded and there were serious attempts to bring relief and achieve a settlement.

Britain played a leading role in establishing a humanitarian ceasefire, but then backed the US cruise missile attack on Khartoum's El Shifa pharmaceutical factory, leading to a break in diplomatic relations.

Despite the ceasefire (only implemented in parts of Bahr el Ghazal), the food security situation has scarcely improved. The UN estimates that Operation Lifeline Sudan will need to continue supplying emergency food relief for two million people in the South.

UNICEF spokeswoman Sally Burnheim said: "The situation remains exteremely critical and people are living dangerously close to the edge. Millions remain dependent on outside assistance."

Neither side has made much headway over the past year. Offensives by both have been repulsed. The SPLA's siege of Torit in Eastern Equatoria ended in failure. In the North, Khartoum's stranglehold on the SPLA-controlled Nuba Mountains was lifted in December, with the recapture of the airstrips essential to supply the beleaguered population.

The government strategy had been to remove the rebel enclaves north of the border as a prelude to entering negotiations on the fate of the South and has therefore prevented any humanitarian assistance from reaching civilians in rebel-held areas of the North.

Thus the strategic impasse continues, with neither side strong enough to achieve either military victory or a strong enough negotiating position to enter into meaningful peace talks. Another aspect limiting negotiations is the alliance between the SPLA and the northern members of the NDA, which currently precludes any settlement for the South alone - despite the protestations of many Southerners.

Internationally, the growth of fighting on its borders will almost certainly have a long term impact on the conduct of Sudan's civil war, which risks becoming just one element of a tangled conflict that stretches all the way from the Indian Ocean to the Atlantic.

The simmering Ethiopian-Eritrean border war has undermined crucial political, military and logistical support for both the NDA and the SPLA as two of their main sponsors continue to rattle sabres at each other rather than at their mutual enemy, Khartoum. The conflict has also reduced the capacity of Sudan's neighbours in the Inter-Governmental Authority for Development (IGAD) to continue to focus on a solution to Sudan's civil war.

The internationalisation of the war in Congo has also made a difference. As more countries get sucked into the conflict in the Great Lakes, the knock-on effects are making themselves felt. Sudan now finds itself allied with both ideological and military opponents in defence of Laurent Kabila's fragile regime in Kinshasa.

Zimbabwe, like Eritrea, had been a strong supporter of Sudan's opposition, but are now on the same side as Khartoum in the Congo, alongside Angola, Namibia, Egypt and Central Africa. Ranged against them are the SPLA's main backers Uganda and Rwanda. This has coincided with a renewal of fighting in Angola, with Jonas Savimbi's UNITA rebels fighting to preserve their supply lines through the Congo.

The merging of these overlapping conflicts has led to some strange realignments and the extension of proxy wars (such as Khartoum's support for the Ugandan Lord's Resistance Army in retaliation for Kampala's support for the Sudanese rebels) resulting in the once fiercely anti-colonial SPLA being on the same side as UNITA.

US policy towards Iraq and Islamic fundamentalism has also backfired in some ways, bolstering pan-Arab support for the hitherto unpopular regime in Khartoum. In August, the opposition's original joy at receiving military support from Washington was soon replaced by concern as a wave of nationalist fervour and anti-Americanism swept across north Sudan and international condemnation was mainly directed at the United States rather than against Khartoum.

On the domestic front, the biggest change in recent months has been a series of defections and infighting on both sides in the conflict, particularly Kerubino Kwanyin Bol's re-defection to the government in December following an apparent assassination bid against Garang.

The strange case of this maverick warlord exemplifies the tragedy of the war. Having originally founded the SPLA in May 1983, Kerubino was imprisoned by Garang for six years before escaping and joining the dissident faction of the rebels and then rejoining the government army. In January 1998, his re-defection to the guerrillas appeared to turn the tide of the war towards the SPLA, yet led to mass famine in his home area of Bahr el Ghazal. Last summer some 70,000 people died of starvation before relief stabilised the situation.

In November, continued rivalry and animosity towards the current rebel leadership led to fighting in Nairobi between Kerubino's supporters and those of Garang. In January, Kerubino resurfaced in Mankien on the border of Bahr el Ghazal and the oil-producing region of Western Upper Nile, with another maverick warlord, Paulino Matip.

As New African went to press, he appears poised to attack Bahr el Ghazal, and aid workers fear a replay of last year's tragedy if the local ceasefire fails to hold and Khartoum attempts to use his re-defection to reverse its military losses in the region.

Another humanitarian catastrophe appears to be looming in Upper Nile, an area cut off by infighting. Since several factions joined Khartoum in 1997 in return for vague commitments towards self-determination, they have been contesting the leadership (accounting for Kerubino's short-lived return to the SPLA). Paulino's refusal to serve under Riek Machar, the nominal head of the South Sudan Defence Force, caused such repeated feuding that last November the bodyguards of all the Southern leaders in Khartoum were disarmed by government security forces.

Large numbers of Riek's soldiers then re-defected, following SPLA information secretary John Luk Jok's announcement: "The leadership of the SPLA would like to take this opportunity to assure all former officers, NCOs and men of the SPLA who joined the NIF under the so-called Khartoum Agreement, which is now dead, to join the SPLA without hesitation."

John Luk was himself a former dissident, having sided with Riek and Lam Akol in the 1991 split in the rebel movement before returning to the mainstream. There is mounting speculation whether Riek will now also attempt to rejoin the SPLA.

With the continuing confusion caused by these shifting allegiances and the deteriorating regional situation, the outlook for Sudan's population remains bleak. Unless concerted international pressure is brought to bear on all sides of the conflict, and a meaningful ceasefire negotiated, 1999 could see even more suffering than the year before.