An Iranian delegation was in North Korea on Tuesday for talks, the two sides putting forward a "common front against imperialism and hegemony", state media said.
Iranian Deputy Foreign Minister Abbas Araghchi met ceremonial head of state Kim Yong-Nam in the capital Pyongyang, the official Korean Central News Agency (KCNA) said.
North Korea and Iran are subject to international sanctions over their nuclear activities and the two countries' governments share a deep hostility towards the United States.
Pyongyang is also suspected of transferring banned ballistic missile technology to Tehran.
Araghchi "expressed belief that the friendly and cooperative relations between the two countries would grow stronger in the future", according to KCNA, which gave little detail of what was discussed.
Kim Yong-Nam serves as de facto head of state because North Korea's founding leader Kim Il-Sung, who died in 1994, has been declared eternal president.
The founder passed on power to his son Jong-Il, who died suddenly in December. His son Jong-Un took over.