Russia's foreign ministry said Thursday it had summoned envoys of Germany, Denmark and Sweden to express "bewilderment" over Moscow's exclusion from an investigation into leaks on the Nord Stream pipelines.
Multiple leaks were discovered on the Nord Stream 1 and 2 pipelines connecting Russia to Germany, further raising political tensions already sky-high since the Kremlin sent troops to Ukraine in February.
Russian President Vladimir Putin has said the leaks were an act of "international terrorism" that would benefit the United States, Poland and Ukraine.
"The heads of the diplomatic missions of Germany, Denmark and Sweden in Moscow have been summoned to the Russian foreign ministry in recent days," the ministry said in a statement.
The ministry said it "expressed bewilderment" over the lack of an official response to a request from Russia's Prime Minister Mikhail Mishustin to involve Russian energy giant Gazprom and "representatives of the competent departments" from Russia in the investigation conducted by Berlin, Copenhagen and Stockholm.
"At the same time, there are reports that other countries including the United States are participating in the probe," it added.
The envoys were told that if Russian experts are not involved "Moscow will proceed from the fact that the named countries have something to hide or they are covering for the perpetrators of these terrorist acts", the ministry said.
It added that Russia will not recognize any "pseudo-results" of an investigation without its experts.