US President George W. Bush and Japanese Prime Minister Junichiro Koizumi warned North Korea on Friday it would face "tougher measures" if it escalates a crisis over its nuclear weapons program.
Both leaders said they believed a peaceful solution was possible, and Bush suggested cash-strapped North Korea could receive "help" if it gave up its nuclear ambitions.
"We are confident that our diplomatic approach will bring a peaceful solution. Yet we agreed that further escalation of the situation by North Korea will require tougher measures from the international community," Bush told a news conference with Koizumi.
Koizumi repeated Bush's warning, though neither leader identified specific measures. US officials have been considering sanctions including a crackdown on North Korea's illegal drug trade and the flow of parts for its missiles.
"Japan will crack down more rigorously on illegal activities, and the North Koreans will have to understand that threats and intimidations will have no meaning whatsoever," Koizumi said.
Japan's ruling Liberal Democratic Party has discussed making it harder for people such as pro-Pyongyang Koreans to send cash to North Korea.
Japan also appears to be cracking down on companies that illegally export products to North Korea that could be used in unconventional weapons.
Steps by North Korea that could trigger new measures could include reprocessing of plutonium to produce fuel that could be used in nuclear weapons, or rocket launches toward Taiwan, a US official said. Possible responses could vary depending on the form of escalation.
White House spokesman Ari Fleischer said "all options" would be on the table.
Koizumi, who favors a peaceful resolution, said Bush had made clear "our response to North Korea would be different from that to Iraq."
The crisis over North Korea erupted in October when Washington said North Korea had admitted to a secret program to enrich uranium for nuclear arms, in addition to a plutonium program frozen under a 1994 US-North Korea pact.
US officials said North Korea told the US, at talks hosted by China last month, that it had nuclear arms.
"The prime minister and I see the problem exactly the same way. We will not tolerate nuclear weapons in North Korea. We will not give in to blackmail. We will not settle for anything less than complete, verifiable and irreversible elimination of North Korea's nuclear weapons program," said Bush, who hosted Koizumi at his Texas ranch.
Bush held out hope of a thaw, praising China's participation in "saying to North Korea that acceptance by the international community and potential help will come when they change their behavior and their attitude toward nuclear weapons."
"This message has been delivered, and the North Koreans are thinking about it," he said.
Bush said the US and Japan would "accelerate" missile defense cooperation -- which a US official said was made more pressing by "the North Korean menace." Bush also backed Japan's aim for a full accounting of Japanese citizens kidnapped by North Korea in the 1970s and 1980s.
The 547-hectare ranch is a favorite hideaway of Bush's for hosting foreign leaders -- and thanking those like Koizumi who supported the US-led war on Iraq.
The meeting came nine days after Bush met South Korean President Roh Moo-hyun in Washington. The two said they would "not tolerate nuclear weapons in North Korea."