U.S. National Security Advisor Condoleezza Rice says she is optimistic that multilateral talks will help convince North Korea to give up its nuclear weapons program. Ms. Rice also repeated Washington's call on Liberian President Charles Taylor to give up power.

A day after meetings with President Bush at his Texas ranch, Ms. Rice spoke at a journalism convention in the city of Dallas where she urged North Korean leader Kim Jong Il to stop developing nuclear weapons.

Ms. Rice says the North Korean leader "doesn't have many choices" as he wants his country more involved in the economic benefits of the international community but must first give up his nuclear weapons program.

Ms. Rice says six-way talks now expected to be held in China will give the United States the opportunity to make that case to North Korea with the backing of diplomats from South Korea, Japan, Russia, and China.

"The only way to convince the North Koreans that they are going to have to give up their ambitions as well as their weapons programs is to have all of the regional powers prepared to tell them that," she said. "It's not enough for the United States to tell them that alone, and so we are actually hopeful that these talks are going to work."

Asked what lessons for North Korea the Bush administration has drawn from its invasion of Iraq, Ms. Rice says the standoff with Pyongyang is an example of what happens "when you let a threat go too long."

She says North Korea has been trying to acquire nuclear weapons technology since the early 1970s. That has multiplied, she says as "nobody was ever able to do anything about the North Korean nuclear threat."

Fortunately, Ms. Rice says regional powers are now arrayed to bring unified pressure on North Korea to stop its nuclear weapons program. The lesson from Iraq, she says, is "don't let it get to that point."

Ms. Rice also discussed civil war in Liberia where she says President Charles Taylor must follow through on promises to step down now that West African peacekeepers have arrived in the capital, Monrovia.

President Taylor has "done enough harm to his country," she says, and it is time for him to leave.

"There have been very sensitive discussions with him by a number of African leaders, and I believe that everybody is giving him the same message: not only must he step down but he must leave the country," Ms. Rice said.

Mr. Taylor has given conflicting signals over the last few months about his willingness to give up power, in part, because he is facing war crimes charges for his involvement in neighboring Sierra Leone.

The Bush administration says it supports that indictment. Ms. Rice says the charges are something Mr. Taylor will have to deal with once he has left the country.