She is also pressing for agreement that any international troop presence to be sent into the province to police a peace deal must also provide security for on-site investigations into allegations of genocide, crimes against humanity and war crimes.
Human Rights organisations believe there is now documented evidence of at least 27 atrocities and massacres carried out in Kosovo since the conflict began in early 1998.
The New York-based Human Rights Watch published a list yesterday of what it says are the main war crimes perpetrated during this period both by Serb forces and the KLA although it says the "vast majority" of the violations over the past year are attributable to the Serbian police or to the Yugoslav army.
The KLA is primarily suspected of kidnappings and summary executions.
The list includes last September's massacre of 21 members of the Delijal family including women and children as young as 18 months old in the village of Gornje Obrinje, the execution of 62 villagers in the village of Bela Crkva last month and the slaughter of 47 Kosovo Albanian men in a violent depopulation campaign in the western city of Djakovica during the first week of April.
Researchers say the list is "far from exhaustive". Britain and Germany have already agreed to hand over intelligence files, which can be used in court.
"We are developing in quite explicit terms what our operational needs will be if and when Kosovo is reopened and there is an international presence," Ms Arbour said yesterday. "We will be reasserting our entitlement to conduct on-site investigations".
Ms Arbour was refused entry to Kosovo earlier this year when she attempted to lead a team of investigators to the site of an alleged massacre at Racak in which 45 ethnic Albanians were killed by the Serbian special police.
The war crimes tribunal in The Hague faces a difficult battle to secure convictions on the basis of witness testimony alone. Ms Arbour also needs as much military intelligence as possible so that those who ordered atrocities can be pinpointed and arrested.
"We have verified enough to feel we have passed the phase of unsubstantiated allegation but that does not reveal much about the perpetrators," she said, adding: "People in the field collect information from witnesses. Governments can help on the issue of command and control."
Ms Arbour said it was crucial to look beyond reports of ethnic cleansing and to gather firm evidence of crimes that fall within its remit - genocide, crimes against humanity and war crimes.Reuse content