Speaking at the end of a six-day visit to the country, Louise Arbour said the casualties were eroding public trust.
She also called for greater safeguards in the way Nato-led forces transferred their detainees into Afghan custody.
Earlier, Oxfam said half of the 1,200 civilian deaths this year were caused by international and Afghan troops.
The UK-based international aid agency also criticised the way aid was distributed in Afghanistan, saying that too much was provided in ways that were ineffective or inefficient.
The report, prepared for a UK parliamentary committee, concluded that too much aid was absorbed by profits for companies or subcontractors, or spent on high salaries and living expenses for expatriate staff.
International standards
Speaking to the BBC in Kabul at the end of a six-day visit, the UN high commissioner said their was no justification for the level of civilian casualties in Afghanistan.
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In law, all sides are held to the same international standards
Louise Arbour UN High Commissioner for Human Rights |
But while she criticised insurgents for using suicide bombings and human shields, Ms Arbour said public opinion was clear - there was a higher expectation of international forces to do everything possible to avoid killing or injuring civilians.
Mrs Arbour said commanders of the Nato-led International Security Assistance Force (Isaf) recognised the significance of the issue and the need to change tactics.
But she said that even if numbers diminished, it was likely civilian casualties would still occur. She also stressed that Isaf the need to give adequate compensation to the victims and their families.
"In law, all sides are held to the same international standards," she said.
"In public opinion... there's an expectation, in a sense higher expectations on behalf of international forces. That being said, the legal standard is exactly the same."
'Considerable risk'
Ms Arbour also said she would support starting peace talks with insurgent groups such as the Taleban.
"Having gained on their security, [people] would crave the freedom that I think, since 2001, has started in little bits to flourish in the democratic system here," she said.
"Now, if all anti-government forces could be brought into the fold of the democratic process, that's the ultimate good-case scenario."
The UN high commissioner later raised concerns about whether Isaf was turning detainees over to torture in Afghan custody.
"I think it's really critical that this issue be looked at, and Isaf collectively, the Nato command, should also take ownership of that issue," she said.
"So far it's been left to the various troop-contributing governments to deal with the issue as they saw fit," she added.
"Their international obligations of non-refoulement mean that anybody they take into detention, they have a responsibility not to turn over if there is a risk of torture, and I think the documentation now shows there is a considerable risk."
http://news.bbc.co.uk/go/pr/fr/-/2/hi/south_asia/7104804.stm
Published: 2007/11/20 23:08:22 GMT
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