A Russian official has told Japanese Prime Minister Junichiro Koizumi that a softer approach may be the best way to resolve the growing dispute over North Korea's nuclear ambitions. But a senior official traveling with Mr. Koizumi in Russia indicates Tokyo may soon take a harder line against Pyongyang.

A senior member of Prime Minister Junichiro Koizumi's government says North Korea is playing "a dangerous game" by withdrawing from a treaty to control nuclear weapons and threatening to restart missile tests.

Deputy Chief Cabinet Secretary Shinzo Abe, who is traveling with the prime minister in Russia, spoke on a Fuji Television news program Sunday. He said tougher action may be needed against Pyongyang. Mr. Abe said that if North Korea keeps escalating matters, world opinion would change in favor of imposing sanctions, rather than trying to resolve the matter through dialogue. He added that possible sanctions would include barring visits by a North Korean cargo and passenger vessel, which regularly calls at Niigata.

Prime Minister Koizumi is wrapping up a trip to Russia with a visit to Khabarovsk in the Russian east. Sunday, he met with the Kremlin's top official there, Konstantin Pulikovsky, who has close ties to North Korean leader Kim Jong Il.

Mr. Koizumi's aides say Mr. Pulikovsky suggests that negotiations with Pyongyang might go smoother if other leaders treat North Korean leader Kim Jong Il as an equal partner. The Russian official reportedly said that Mr. Kim will resist efforts to pressure him into complying with international treaty commitments.

Pyongyang on Friday said it was withdrawing from the Nuclear Non-proliferation Treaty. A day later, North Korea's ambassador in Beijing indicated that Pyongyang may end its moratorium on missile testing. Pyongyang's missiles are believed to be capable of reaching South Korea and Japan.

However, on Saturday, two North Korean diplomats told a U.S. politician their country has no intention of building nuclear weapons.

Tension has been increasing on the Korean Peninsula since October, when the United States said North Korea had admitted having an illegal nuclear weapons program. Since then, the United States and its allies have cut off fuel aid to the impoverished country and North Korea has begun reactivating a nuclear program it had promised to shut down.