In this file photo, Russian Foreign Ministry spokeswoman Maria Zakharova speaks to the media in Moscow on March 29, 2018. (YURI KADOBNOV / AFP)

MOSCOW - Russia’s foreign ministry said on Tuesday it had summoned the German ambassador to Moscow over statements made by Berlin on the situation concerning Russian opposition politician Alexei Navalny.

Germany has concluded Navalny was poisoned with the nerve agent Novichok

Navalny, 44, was airlifted to Germany last month after collapsing on a flight from the Siberian city of Tomsk to Moscow. Germany has concluded he was poisoned with the nerve agent Novichok.

Foreign ministry spokeswoman Maria Zakharova accused Germany of “bluffing” in a statement posted online.

ALSO READ: Kremlin denies involvement in suspected poisoning of Navalny

“It’s time to show your cards,” Zakharova wrote on Facebook. “Berlin is bluffing in the service of a dirty political commotion.

In Berlin, German Chancellor Angela Merkel intends to coordinate any action against Russia with European partners, ruling out a unilateral response.

Merkel made the comments at a closed-door meeting of her Christian Democratic-led parliamentary caucus on Tuesday, according to an official who asked not to be identified in line with briefing rules. 

Merkel indicated that she hasn’t made a final decision on whether the controversial Baltic Sea pipeline from Russia will be affected by any action against Moscow, the official said.

A top medical official in the Siberian region where Navalny was initially treated before being sent to Germany challenged Berlin’s account of his illness Tuesday.

The cause “definitely wasn’t Novichok, there are no signs of poisoning,” Alexander Sabayev said, according to the state-run RIA Novosti news service. “This wasn’t a poisoning at all. It’s an illness,” he said, reiterating Russian assertions that Navalny suffered from a “metabolic disorder.”

With inputs from Reuters