Foreign Minister Heiko Maas said Sunday that Germany was planning to discuss possible sanctions on Russia over the poisoning of Russian opposition leader Alexei Navalny.

"If in the coming days Russia does not help clarify what happened, we will be compelled to discuss a response with our allies," Maas told Bild newspaper. Any sanctions decided should be "targeted," he added.

Read more: Opinion: In wake of Navalny attack, what will become of German-Russian relations?

Germany, which holds the rotating presidency of the European Union, is under pressure to act strictly with Russia over Navalny's poisoning. Navalny fell ill on a flight last month and was treated in a Siberian hospital before being evacuated to Berlin.

Earlier this week, the German government announced that Navalny had been poisoned with the military-grade nerve agent Novichok, the same chemical weapon British authorities say was used against Russian double agent Sergei Skripal and his daughter in 2018.

'Several indications' Kremlin behind poisoning

The Russian government has denied responsibility for the attack on Navalny, with Foreign Minister Sergey Lavrov saying that Berlin has yet to share any findings with Russian prosecutors.

But according to Maas, there were "several indications" that Russia was behind the poisoning.

"The deadly substance with which Navalny was poisoned has in the past been found in the hands of Russian authorities," he said. "Only a small number of people have access to Novichok, and this poison was used by Russian secret services in the attack against former agent Sergei Skripal," the minister said.

Read more: Navalny poisoning: Confronting Russia, EU has limited options

Maas also didn't rule out sanctions against the disputed €10-billion ($11-billion) Nord Stream 2 pipeline, which is under construction to deliver Russian gas to Europe.

"I hope... that the Russians do not force us to change our position on Nord Stream," he said, adding that the consequences of any potential scrapping of the project would be assessed and that the debate on sanctions should not be "reduced" to a single point.

NATO calls on Russia to cooperate with investigation

NATO Secretary-General Jens Stoltenberg has called on Russia to fully cooperate with an "impartial investigation" led by the Organization for the Prohibition of Chemical Weapons (OPCW) into Navalny's poisoning.

Read more: NATO calls for 'international response' over Navalny poisoning

Responding to a question from DW correspondent Teri Schultz in Brussels on Friday, Stoltenberg said NATO's response to the poisoning stems from the illegal use of a chemical weapon banned under international law and norms.

Speaking to reporters on Friday, US President Donald Trump said Washington did not have any evidence of Navalny's poisoning. "I don't know exactly what happened. I think it's tragic, it's terrible, it shouldn't happen," he said.

"We haven't had any proof yet, but I will take a look at it," Trump said at a White House press conference.

shs/rc (AFP, Reuters)