United Nations Secretary General Ban Ki-moon says stopping the killing and finding a political solution in the Darfur region of Sudan remain his highest priorities. VOA's Sonja Pace reports from London, the U.N. chief has been meeting with Middle East peace envoy Tony Blair.

Speaking at London's prestigious Chatham House research center, U.N. chief, Ban Ki-moon described the humanitarian crisis in Darfur as "devastating," and said the world can no longer accept further delays in the peace process.

"The tragic cycle of violence has been allowed to continue for too long," he said. "I think the people in Darfur have suffered too much. The international community has waited too long."

After increasing international pressure, the Sudanese government last month agreed to allow a combined 20,000-strong peacekeeping force, made up of the U.N. and the African Union, into Darfur. Mr. Ban said this was progress.

Speaking in Washington on Wednesday, U.S. Secretary of State Condoleezza Rice warned, however, that the Khartoum government must not be allowed to continue playing what she called a cat and mouse game over ending the violence.

It is estimated that some 200,000 people have died in Darfur's ethnic and political conflict since 2003.

In London, Mr. Ban also met with the new Middle East peace envoy Tony Blair. Mr. Blair has been named the representative of the Middle East Quartet, which is made up of the United States, the European Union, the U.N. and Russia.

Mr. Ban said there is widespread concern about the Palestinian factional fighting and the deteriorating humanitarian situation in Gaza. He also expressed concern over the divisive political situation in Lebanon and the ongoing violence in Iraq. And he issued a warning.

"However [much] military action may be effective, there is always a limitation unless they are accompanied by political dialogue and reconciliation amongst themselves," he said.

Mr. Ban cited a number of other global issues the U.N. is dealing with, including North Korea, Iran and terrorism. And he cited another problem that, he said, concerns all of mankind - climate change.

"I'm convinced that this challenge and what we do about it will define us, our era and ultimately our global legacy," said Ban.

Mr. Ban cautioned that the U.N. cannot be everywhere and cannot provide all the answers, but he said it can provide a forum for finding solutions.