Both sides have been recruiting new soldiers -- sometimes by force and including children
Despite a brief truce, hopes for peace have crumbled in South Sudan as its civil war hits the three-year mark with ethnic violence only getting worse and no end in sight.
"South Sudan's war continues to escalate and engulf more and more of the country," said Alan Boswell, an independent analyst, who expects further major offensives with the imminent start of the dry season.
The international community, which strongly backed the country's drive to independence in 2011, has been powerless to stop the worsening violence, with the UN issuing stark warnings of potential genocide and ethnic cleansing.
Both sides have been recruiting new soldiers -- sometimes by force and including children -- and are preparing for full-on war, said Boswell, while diplomats struggle with how to prevent it.
"There's no actual peace process or political plan right now. So there is no framework for the international community to even pressure the parties to stop," said Boswell.
"The international community has more less accepted that (more) fighting is about to break out," he added.
War broke out on December 15, 2013 when President Salva Kiir accused his former deputy and political rival, Riek Machar, of plotting a coup.
A peace agreement signed two and a half years later raised hopes of an end to a conflict marked by atrocities which has left tens of thousands dead and more than three million displaced.
The deal's implementation, however, lasted just over two months.
Machar returned to the capital Juba in late April to form a government of national unity with Kiir, but violent clashes broke out in July, leaving hundreds dead.
Machar was forced to flee through the jungles of the Democratic Republic of Congo, and is now exiled in South Africa -- isolated but still the bellicose leader of the rebellion.
After its outbreak in Juba the war was largely restricted to the northern states of Unity, Upper Nile and Jonglei but has in recent months expanded into the southern Equatoria region surrounding Juba.
As the rains draw to a halt and the traditional fighting season is set to start, Kiir on Wednesday called for a "national dialogue" in a speech to parliament, urging an end to hostilities and calling for forgiveness "for any mistakes I might have committed".
However he made no mention of his foe Machar and it is unclear how his call would be received by the rebels.
Neither side able to win
Ethnic killings have intensified in recent months, particularly in and around the southern town of Yei, pushing tens of thousands of people to seek refuge in neighbouring Uganda.
These atrocities have drawn the attention of the international community with UN experts in early December reporting "ethnic cleansing" in several parts of South Sudan.
Weeks earlier the UN Special Adviser on the Prevention of Genocide, Adama Dieng, warned of "a strong risk of violence escalating along ethnic lines, with the potential for genocide."
That view is widely held.
"What is happening now, there is clear ethnic targeting and if it grows, if it becomes massive, it will not be different to what happened in Rwanda," said James Okuk, a political analyst at the University of Juba, referring to the 1994 genocide.
Neither government nor rebel sides seem able to win militarily or to turn battlefield gains into political ones.
In southern Equatoria, "now the main theatre of the war... the government basically has almost no control outside of a few garrison towns," said Boswell.
But at the same time, "the rebels have proven unable to actually launch offensives against major government strongholds," because they are "way, way out-resourced" by the government.
"The government is militarily stronger but politically weaker," said Boswell, while "the rebellion has strong sympathies in much of the country, yet militarily the rebels are quite weak."
International pressure forced the South Sudanese government to accept the proposed deployment of an additional 4,000-strong UN "protection force", but months later it remains on paper only and the fighting continues.
The key to peace, said Boswell, lies with South Sudan's neighbours, if they can find common ground.
"South Sudan's regional neighbours could stop this, really, at any time if they wanted to and collectively saw the interest. The problem is that their interests are often competing," he said.
Since July's fighting there has been diplomatic disarray, with no regional policy or agreement on what to do. Foreign powers, led by the US, that were heavily involved in ending the long war with Sudan and then ushering in South Sudan's independence in July 2011 seem equally at a loss.
"The US basically doesn't have a policy on South Sudan right now," said Boswell, and that has left "a huge vacuum for international policy".