China has provided information and documents to a joint investigation into two severed Baltic Sea undersea cables, and has invited Germany, Sweden, Finland and Denmark to participate in and complete the inquiry, the Foreign Ministry said on Monday.

Foreign Ministry spokeswoman Mao Ning made the remarks at a news briefing when asked about a Financial Times report that Sweden had criticised China for refusing full access despite an open investigation, and for not allowing its public prosecutor to board the suspect ship, Yi Peng 3.

The Chinese bulk carrier is moving again after sitting still for more than a month in Danish waters, the Swedish Coastguard said on Saturday. China allowed representatives from Germany, Sweden, Finland and Denmark to board the vessel for the investigation last week.

"In order to cooperate with the investigation, the Yi Peng 3 has been suspended for a long period of time, and in order to safeguard the physical and mental health of the crew, the shipowner company has decided to resume its voyage after a comprehensive assessment and consultation with the parties concerned," Mao said.

She added that China had notified all relevant countries in advance and was willing to maintain communication and cooperation.

Yi Peng 3 came under investigation following the breach in November of two fibre-optic cables - one linking Finland and Germany and the other connecting Sweden to Lithuania - that raised suspicions of sabotage and concerns about the security of critical infrastructure. (Reuters)