"We, as the German government, fully trust the assessment of UK and Dutch authorities. The German government believes that it is highly probable that the Russian military intelligence GRU is behind APT28 campaign. This assessment is based on our own very good facts and sources," Seibert said.
The statement follows accusations voiced by Dutch Defense Minister Ank Bijleveld on Thursday: he stated that four Russian citizens had been expelled from the Netherlands in April on suspicion of an attempted cyberattack on the Organization for the Prohibition of Chemical Weapons (OPCW).
READ MORE: Russia to Summon Dutch Ambassador Amid Hacking Accusations — Source
Meanwhile, the UK Foreign Office said Thursday that the Russian military intelligence service GRU was "almost certainly" responsible for a series of cyberattacks on political institutions, media outlets and infrastructure across the globe, including in the United Kingdom. The UK National Cyber Security Centre listed names of entities it believes are associated with the GRU, including APT 28.
READ MORE: Alleged Russian Hackers Suspected of Stealing Belgian Report on Ukraine — Report
The Russian Foreign Ministry refuted the claims on Thursday and stressed that the "spy mania campaign" unleashed in the Netherlands was seriously hurting bilateral relations with Russia. The ministry pointed out that the Netherlands made the statement ahead of the OPCW opening session, which could set up the "'necessary' political background" to push through some initiative. According to the ministry's commentary, the OPCW is set to discuss the financing for the mechanism which would allow the OPCW to attribute guilt. Russia has been against the initiative.
READ MORE: Moscow Slams Netherlands' Claims of Russia's Attempted Hacker Attack on OPCW
US Assistant Attorney General for National Security John Demers said Thursday that the United States had filed charges against seven alleged Russian military intelligence officers for taking part in a conspiracy to hack US, Canadian and international organizations. Four of the suspects were the same Russian citizens that Amsterdam expelled.
Russian Deputy Foreign Minister Sergey Ryabkov expressed regret over the US authorities' continued attempts to "poison the atmosphere of Russia-US relations with new portions of baseless accusations against Russia, which some other NATO countries rush to repeat on orders from Washington."