Washington: The US Treasury announced sanctions on Russian and Chinese companies for violating the economic embargo on North Korea as Washington seeks to keep pressure on Pyongyang over its nuclear programme.

The Treasury accused China-based Dalian Sun Moon Star International Logistics Trading Co and its Singapore-based affiliate, SINSMS Pte., of falsifying documents to facilitate "illicit" shipments of to North Korea.

It said that Russia-based Profinet Pte. violated United Nations sanctions by providing port services to sanctioned North Korean-flagged ships at three eastern Russia ports.