"When we are faced with deliberate organized campaigns to murder whole people or expel them from the land, the care of the victims is important but not enough," the president said.
"We should work to end the violence," he said. He said the U.N. should use collective military force at times, diplomacy and sanctions on other occasions. But, he warned, "We cannot do everything everywhere."
His voice was hoarse, breaking at times, apparently because of allergies. Secretary of State Madeleine Albright and National Security Adviser Sandy Berger were in the audience for his address.
Mr. Clinton opened his remarks by urging world leaders to "wage an unrelenting battle against poverty and for shared prosperity so that no part of humanity is left behind in the global economy."
He said 1.3 billion people live on less than $1 a day.
"More than half the population of many countries have no access to safe water. A person in south Asia is 700 times less likely to use the Internet as someone in the United States. And 40 million people a year still die of hunger, almost as many as the total number killed in World War II."
The president wants to encourage new steps to fight poverty and disease - to close what he's calling a "health gap" that's leaving developing countries behind, CBS News White House Correspondent Bill Plante reports.
Mr. Clinton said he would convene a White House conference of public health experts, pharmaceutical companies and foundation representatives to encourage production of vaccines for developing countries.
"Each year diseases like malaria, tuberculosis, pneumonia, leave millions of children without parents, millions of parents without children," the president said. "Yet for all these diseases, vaccine research is advancing too slowly, in part because the potential customers in need are too poor."
Mr. Clinton said that only 2 percent of global biomedical research is devoted to the worst diseases in the developing world. "No country can break poverty's bonds if its people are disabled by disease and its government overwhelmed by the needs of the ill," the president said.
Mr. Clinton also said U.N. members share an obligation to stop the spread of nuclear, biological and chemical weapons.
In particular, Mr. Clinton urged world leaders to keep pressure on Iraqi President Saddam Hussein to abandon its suspected weapons program.
"Now we must work to deny weapons of mass destruction to those who would use them," the president said. "For almost a decade," he said, "nations have stood together to keep the Iraqi regime from threatening its people and the world with such weapns.
"Despite all the obstacles Saddam Hussein has placed in our path, we must continue to ease the suffering of the people of Iraq," Mr. Clinton said. "At the same time, we cannot allow the government of Iraq to flout 40 and I say, 40 successive U.N. Security Council resolutions and to rebuild his arsenal."