The United Nations Security Council has voted to send peacekeepers to the war-ravaged Darfur region of Sudan, after months of wrangling.
African Union soldiers will be part of the UN force in Darfur
Up to 26,000 troops and police will make up the world's largest peacekeeping force, under a joint UN and African Union mandate.
The resolution will allow peacekeepers to use force to defend civilians and aid workers in Darfur from attack.
At least 200,000 people are thought to have died in the region since 2003.
More than two million have fled their homes over the same period, since rebel groups rose up against the Khartoum government's rule.
Sudan's government and the pro-government Arab militias are accused of war crimes against the region's black African population, although the UN has stopped short of calling it genocide.
'Clear and powerful signal'
Under the new resolution, the first peacekeeping troops will begin arriving in October.
UN Secretary General Ban Ki-moon described the mission as "historic and unprecedented".
He told the Security Council: "You are sending a clear and powerful signal of your commitment to improve the lives of the people of the region, and close this tragic chapter in Sudan's history."
But the toning down of the resolution's language, after Sudan's UN ambassador described an early draft as "ugly" and "awful", sparked criticism from American senators.
Democrat Russ Feingold, who chairs the Senate foreign relations sub-committee on Africa, said: "I am very disappointed that the resolution's co-sponsors have succumbed to pressure from the Sudanese government."
The unanimous vote came after negotiations secured crucial Chinese support.
'Faithful and honest'
The peacekeeping mission, to be known as Unamid - the United Nations African Union Mission in Darfur - is expected to cost up to $2bn (£1.1bn) a year.
The situation in Darfur has caused many to flee their homes
It will come together over the final months of 2007, with the aim of being in charge of operations in Darfur by the end of the year.
The Sudanese ambassador to the UN, Dr Abdelmahmood Abdelhaleem Mohamed, said his country would fulfil its obligations under the resolution.
He told the BBC: "We will be committed, we will be faithful and honest to our obligations."
A joint African Union-UN meeting in Arusha, Tanzania, will try later this week to establish a framework for peace talks between the Darfur rebels and Sudanese government.