"We don't know what it means, but this is a matter we should take up and question," Löfven told Aftonbladet on Monday. "Whether this has any significance and whether this is a new interest, is something we don't yet know."
The Chinese fleet taking part in the Joint Sea 2017 exercise includes an advanced 052 Destroyers, a frigate, a support vessel, a helicopter and Chinese marines. It will be the first time the Chinese navy has taken part in an exercise in the Baltic Sea.
Lithuanian Foreign Minister Linas Linkevicius has criticised the move as "not setting an example in the field in real life and by way of actions," arguing it could threaten regional stability.
But Russia's Ambassador to China, Andrei Denisov, said that although the exercise was a new development, it was intended to bolster miltary cooperation between the two countries rather than to threaten other countries with Baltic coasts.
"There is a point of novelty, but I haven't heard anyone expressing much concern over this so-called 'threat.'," he said according to the Russian State news agency Tass. "China is interested in ocean navigation, it is kind of a long-distance cruise for them."