SOLDIERS in South Sudan say they are tired. Many have already spent a lifetime fighting in the grassy plain on either side of the Upper Nile. Their country won independence in 2011 after decades of rebellion against the mainly Muslim north, aggravating the destitution of most of its people. But South Sudan’s own ceaseless divisions broke out in civil war a year ago when a coup or a purge—opinions differ—shattered the peace in the world’s youngest country. No wonder that government troops, mutinous soldiers and ragtag tribal militias all sound exhausted.

But not enough to stop fighting. Tanks, artillery and armoured personnel carriers are set to rage back and forth across a land that has few roads, none of them paved, barring some miles in the capital, Juba. The landscape may slow mechanised warfare. The weather is the only thing that has afforded people a respite. For months the rains have been so heavy that much of the land is a quagmire. That has limited fighting to local skirmishes.

Now the rainy season is over, along with the lull. As in every year since 1955, when war first erupted, Christmas time is the start of the fighting season in predominantly Christian South Sudan. John Ruai, an officer in Unity state, near the border with rump Sudan to the north, says by telephone: “We have folded our camp and are moving out.” Government troops have spent the past few months training and ordering up fresh supplies, including ammunition, though most of them will arrive only after the roads are open again as the mud dries, giving a fresh lease of life to the ceaseless fighting.

In the past year thousands of civilians have been killed and almost 2m have fled their homes. Many more face a famine that could become the world’s worst humanitarian crisis, aid workers warn. Around 4m people, close to a third of the population, face grave food shortages. Almost all government funds are being spent on arms.

More than 100,000 refugees have sought shelter in UN bases around the country. Although fed and better off than most in the short run, they still face attacks. At least 60 were injured in fighting at a camp on November 22nd. The president, Salva Kiir, has accused the UN of protecting bloodstained rebels, saying that its bases are hosting his enemies, who are armed and “agitating”. Government troops may take their leader’s accusations as a nod to attack the camps. There are fears of massacres “on the magnitude of Srebrenica or Rwanda”, in the words of a foreign analyst.

The two sides, which have held intermittent peace talks this year, have signed three or four deals meant to stop the fighting. But all have failed. A new round of talks brokered by Ethiopia and due to start this month has been put on hold. The UN Security Council has threatened to slap sanctions on South Sudanese leaders for failing genuinely to seek peace. An arms embargo is under discussion. There is no sign of a breakthrough.

Instead, both the government and the rebels talk again of a military solution. An opposition commander told the International Crisis Group, a Brussels-based lobby: “We will settle this with war.” The next round of fighting may focus on the oilfields along the northern border. They provide almost all the government’s revenues.

By enhancing security around oil installations, the UN favours the government side. But the UN’s 12,500 peacekeepers are sorely stretched. Ellen Margrethe Loj, head of the UN mission, told the Security Council last month that only a comprehensive peace agreement could make South Sudan stable. None is in the offing. Meanwhile, says Ms Loj, “I have been shocked by the complete disregard for human life.”