Annan, who will go to Darfur next week at the start of a three-week trip to the Middle East, Africa, Asia and Europe, said he and US Secretary of State Colin Powell would pressure Sudanese officials to deal with the killings, hunger and
"We will be in Khartoum at least for one day together where we will collectively be putting pressure on the government to do what it has to do," Annan told a news conference on Friday.
But he said he was not ready to "send in the cavalry and I'm not sure I have that many countries ready to go."
However, he noted that troops had been sent to East Timor in 1999 to quell the violence, with Australia in the lead.
Darfur fighting has rendered
"That willingness to go in and help must also be there (for Sudan) and be demonstrated, and I think we should all begin thinking about that," Annan said.
Fighting broke out last year between black Africans and Sudanese government forces and Arab militia, called Janjaweed, in the western Sudanese region of Darfur. Hundreds of thousands of people were forced to flee to neighbouring Chad.
Some 10,000 to 30,000 people are estimated to have died. One million people were forced out of their villages and two million are in desperate need of aid, UN officials say.
"All governments with influence in Khartoum must engage the Government of Sudan and insist that the government must protect its people," Annan said.
"It must disarm the Janjaweed, it must create an environment that will allow the displaced to go home, and it should engage with the rebel side."
Annan said the situation in Darfur "was bordering on ethnic cleansing" but would not use the word genocide.
"We all agree that serious crimes are being committed"
"We all agree that serious crimes are being committed," he said in answer to questions. "We don't need a label to propel us to act, and so I think we should act now and stop arguing about which label to put on it."
A peace agreement with the Khartoum government and rebels in southern Sudan, who have been fighting for two decades, would never hold unless Darfur is settled, Annan said.
"We have made progress on the north-south track, but you cannot have comprehensive peace in Sudan if the west continues to burn," he said. "So we have to settle Darfur to be able to talk of a comprehensive peace in Sudan."
Annan leaves on his trip on Sunday, stopping first in Qatar, where he meets Amir Hamad bin Khalifa Al Thani on Tuesday.