The new leadership of the United Nations is facing a defiant challenge from within one of its few recent successes - the war crimes tribunal in The Hague - over who will steer the epic trials towards their close.
Prosecution lawyers at the International Criminal Tribunal for the former Yugoslavia (ICTY) - trying Europe's bloodiest war criminals since the Nazis - fear a backstage deal has been struck between new UN Secretary General Ban Ki-Moon over an appointment of a successor to chief prosecutor Carla Del Ponte, who leaves in December. Senior Hague lawyers say they are ready to quit over the issue.
Accounts by tribunal and UN sources of how a former Belgian attorney-general petitioned for the job and has reportedly been guaranteed it affords a rare insight into the veiled sanctums of the UN.
Sources at the ICTY, at UN headquarters in New York and across the world of international law and human rights advocacy, say Del Ponte's succession has been pledged in secret to Serge Brammertz, a Belgian criminologist who became deputy prosecutor at the new International Criminal Court and heads the UN commission into the murder of Lebanese premier Rafiq al-Hariri in 2005, which he wants to leave.
The entire senior prosecution staff at the tribunal have taken the unprecedented step of sending a joint letter to Ki-Moon, contesting a Brammertz appointment by proposing Del Ponte's current deputy David Tolbert, who has worked for nine years at the tribunal, for the job.
'The matter is not one of personalities nor Brammertz's standing', says one lawyer. 'It's the difference between someone who knows the history, understands every case and can deliver a completion strategy, or someone brought in by the Secretary General just to shut the tribunal down, with no experience of the cases, background or region.'
Ki-Moon's office will not comment, citing confidentiality of the appointments procedure. But the lawyers' view is backed unanimously by organisations with an interest in the tribunal's work, including the George Soros Foundation, Human Rights Watch and campaigners within former Yugoslavia itself, all of whom have also petitioned Ki-Moon.
'Just because people haven't heard of the names remaining to stand trial doesn't mean that they are not the most important cases,' says Kelly Askin, senior legal officer at the Soros Foundation. 'It's crucial that there be continuity - and the fact is we have someone available who knows the institution and the people, and has followed every case and every detail for nine years. Several senior staff have told me they will leave the tribunal if David Tolbert is not appointed.'
The ICTY has had a bumpy journey since it was established under pressure from then President Bill Clinton's Secretary of State, Madeleine Albright, in 1994. It was seen at the time as an act of contrition after the UN's catastrophic failure to intervene as hundreds of thousands died in three years of savage 'ethnic cleansing' in Bosnia, culminating with the massacre of 8,000 men and boys at the UN-protected 'Safe Area' of Srebrenica in July 1995.
The tribunal lost its biggest catch with the death in prison of former Serbian President Slobodan Milosevic, and is haunted by the failure to catch the two Bosnian Serb leaders accused of unleashing the genocide in Bosnia - General Ratko Mladic and former President Radovan Karadzic. Their capture would extend the tribunal's mandate beyond 2010, and make for a climactic end-game; Del Ponte made what could be her final trip to Belgrade this week as a last-ditch attempt to secure, under her watch, the two leaders.
But for all the publicity over Karadzic and Mladic, the tribunal - the first of its kind since the Nuremberg trials - has seen remarkable successes. Even apart from the convictions secured, accounts of the slaughter have been told for the historical record in intimate language from the witness boxes. There have been dramatic moments as killers and leaders have been confronted by victims.
The tribunal won a guilty plea from Karadzic's co-President Biljana Plavsic, for her role in the overall planning of war crimes. New laws of war have been written: the Serb siege of Sarajevo was deemed a war crime, as was the use of systematic mass rape as a means of persecution at Foca, in Eastern Bosnia.
But crucial trials are outstanding or still in process - the leadership of the Bosnian Croat war machine, which laid murderous siege to East Mostar and set up a gulag for Muslims, is currently standing trial; notorious paramilitary warlord Milan Lukic awaits trial, accused of locking scores of families in houses and burning them alive in Visegrad. Above all, Momcilo Peresic - Milosevic's most senior general - is also due for trial. It is a critical case, because a conviction would establish Serbia's direct involvement in the genocide, in stark counterpoint to a ruling by the International Court of Justice, which rejected a case by the Bosnian government against Serbia for its involvement in genocide.
The team that convicted Krstic, Krajsnik and those preparing the cases against Lukic and Peresic all are signatories to the letter to Ki-Moon.
An ICTY statement last week said del Ponte's mandate had been extended until 31 December. 'The successor to the current prosecutor has not yet been appointed yet,' it said.
Mark Ellis, of the London-based International Bar Association, said: 'It struck me as very odd that the UN would make a decision which would in essence put a newcomer in charge.'