BERLIN (AFP) - German Foreign Minister Guido Westerwelle said on Sunday that North Korea must ensure the security of embassies on its soil after Pyongyang warned diplomats that it could not protect them if a conflict broke out.

"Foreign Minister Westerwelle reiterated that any deadline after which North Korea would no longer ensure the security of embassies is unacceptable," his ministry said after he spoke by telephone with Berlin's envoy to Pyongyang.

"There are clear guidelines under international law that are also binding for North Korea. The stoking of tensions by North Korea is irresponsible and a real threat to peace and security in the region."

The ministry repeated a statement from Saturday that Germany's embassy in Pyongyang was still working "for the time being" and that it was continually evaluating its travel and security advisories for the country.

"It is advised to avoid unnecessary travel to North Korea," it said.

Mr Westerwelle said Germany continued to consult with international allies and their ambassadors in North Korea "and seek close coordination with the UN Security Council members China and Russia" on the best approach to North Korea.

"The situation is tense but calm," the ministry said.

Foreign diplomats in Pyongyang huddled at the weekend to discuss a warning from the North's authorities that their safety could not be guaranteed after Wednesday in the event of a conflict.

Most of their governments have made clear they have no immediate plans to withdraw personnel, and some suggested the advisory was a ruse to fuel growing global anxiety over the crisis.