Switzerland has offered to mediate with North Korea as tension rises on the Korean peninsula following U.N. sanctions imposed in response to a nuclear weapon test in February.

The Swiss foreign ministry has made contact with the North Korean authorities, a spokeswoman said, but added that there were currently no plans for any talks.

"Switzerland is willing to contribute to a de-escalation on the Korean peninsula and is always willing to help find a solution, if this is the wish of the parties, such as hosting meetings between them," she said in an emailed statement.

North Korea has issued increasingly strident warnings of imminent war with South Korea and the United States, telling diplomats on Friday to consider leaving Pyongyang.

Neutral Switzerland often mediates in international conflicts or hosts peace talks, in recent years helping broker a deal aimed at resolving a long-running conflict between Armenia and Turkey.

The Swiss Foreign Ministry said it had been involved in more than 15 sets of peace negotiations in the past seven years, including in Sudan, Colombia, Sri Lanka, Uganda and Nepal.

North Korean leader Kim Jong-un, who took over in December 2011 after the death of his father Kim Jong-il, is thought to have spent several years in Switzerland being educated under a pseudonym.