SEOUL, South Korea (AP) -- The top U.S. envoy on North Korea is calling a Chinese bank's decision to close the accounts of Pyongyang's main foreign exchange bank a "very hopeful sign" in efforts to end the North's nuclear ambitions.

Glyn Davies said Monday that it's not yet clear whether this signifies a real shift in Beijing. But he calls the development interesting. Davies meets Tuesday with South Korean officials and then heads for talks in China and Japan.

A torrent of warlike North Korean threats following its February nuclear test has raised inter-Korean tensions.

The state-run Bank of China Ltd. said last week that it halted business with North Korea's Foreign Trade Bank. Washington accuses the bank of financing Pyongyang's missile and nuclear programs. It's the latest sign of Beijing's displeasure with its ally.