NATO has called on a defiant Russia to "fully cooperate" with an "impartial international" probe to be led by the global Organization for the Prohibition of Chemical Weapons (OPCW) into the poisoning of opposition leader Aleksei Navalny.
The 30-member Western military alliance agreed that Russia "now has serious questions it must answer," Secretary-General Jens Stoltenberg told a news conference in Brussels on September 4 following a special session of the organization's ambassadors.
"Any use of chemical weapons shows a total disrespect for human lives, and is an unacceptable breach of international norms and rules," Stoltenberg said.
Germany on September 2 said that toxicology tests provided "unequivocal evidence" that the gravely ill Kremlin-critic had been poisoned with a Novichok, a Soviet-style military-grade nerve agent.
Stoltenberg said the NATO allies demanded Moscow reveal its Novichok program to the OPCW.
Calling the Navalny case "an attack on fundamental democratic rights," he said NATO allies would continue to consult on the incident and "consider the implications."
So far, Russian authorities have resorted to obfuscation and denial in their response to Navalny’s case and have refused to open a criminal investigation into the allegation that the opposition politician was poisoned, saying that no hard evidence has been found.
Navalny, 44, fell ill on a flight from Siberia to Moscow on August 20, forcing the plane he was traveling on to make an emergency landing in Omsk, where he spent two days in hospital before being evacuated to Germany.
He is now on a respirator and under medically induced coma in an intensive-care unit at Charite Hospital in Berlin.
Germany is seeking to forge a joint reaction against Russia from its EU and NATO partners, after Chancellor Angela Merkel describe Navalny’s case as an "attempted murder by poisoning."
In an open letter to EU foreign-policy chief Josep Borrell published on September 4, more than 100 members of the European Parliament called for sanctions against those responsible for attacks against opposition figures and journalists in Russia.
The lawmakers from various political groups called for a "full and transparent investigation" into Navalny's case, but they said they were "extremely skeptical that Russian authorities are fit and willing to investigate the real background of this crime."
Borrell issued a statement on behalf of all EU members on September 3 condemning the "assassination attempt" and demanding Moscow fully investigate the crime.
"The European Union calls for a joint international response and reserves the right to take appropriate actions, including through restrictive measures," Borrell said. "Impunity must not and will not be tolerated."
Borrell demanded Russia "fully cooperate" with the OPCW chemical-weapons watchdog to ensure a full international investigation.
In response to Borrell’s comments, Russian Deputy Foreign Minister Aleksandr Grushko told the EU’s Ambassador to Russia Marcus Ederer on September 4 it was “inadmissible to politicize the given issue and to bring up unsubstantiated accusations,” according to the Foreign Ministry.
Russian Interior Minister Vladimir Kolokoltsev told Interfax he currently saw “absolutely no grounds” to suspect a crime was committed in the Navalny case.
Earlier in the day, Russian media reported that Russia's Investigative Committee had asked one of its regional branches in Siberia to probe the possibility that someone had tried to murder Navalny.
In Moscow, President Vladimir Putin's spokesman said that the Russian authorities want to find out through dialogue with Germany what exact substance caused Navalny to fall ill.
Dmitry Peskov also claimed that Russian doctors who treated him initially were much more transparent than the German doctors, and said Russian specialists were looking into the case.
Meanwhile, the chief toxicologist for the Omsk region in Siberia told Russian journalists that Navalny’s health could have deteriorated due to dieting, stress, or fatigue, and he insisted that no poison had been found in his blood samples taken in the city of Omsk, where the anti-corruption campaigner was treated for the first two days after falling ill.
"The patient used diets to lose weight," the chief toxicologist for the Omsk region, Aleksandr Sabayev, said. "Any external factors could have triggered a sudden deterioration. Even a simple lack of breakfast."
Navalny's top aide, Leonid Volkov, told Current Time on September 4 that the opposition figure was targeted because of his Smart Voting campaign that promotes independent or opposition candidates for upcoming local elections.
"[Navalny's] Smart Voting [campaign] is so dangerous [for Russian authorities] that they are ready to kill for it, because Smart Voting showed and proved that it is an absolutely effective strategy against [the ruling] United Russia," Volkov said, adding that the only way to deal with Navalny's campaign was for the authorities to poison him. Current Time is the Russian-language network led by RFE/RL in cooperation with VOA.
According to Volkov, Russian authorities have tried to stop Navalny's Smart Voting campaign by all possible means as nationwide local elections scheduled for September 13 are getting closer.
He pointed to the campaign's success last year, when United Russia lost about 200 mandates because of Navalny's campaign in regional parliaments during elections.
Pressure is also mounting on Merkel at home to abandon the Nord Stream 2 project, an underwater Baltic Sea pipeline nearing completion that would bring gas from Russia to Germany.
"Diplomatic rituals are no longer enough," Norbert Roettgen, the head of the German parliament's foreign affairs committee, tweeted on September 2.
"After the poisoning of Navalny we need a strong European answer which Putin understands: The EU should jointly decide to stop Nord Stream 2," said Roettgen, a candidate to be the next leader of Merkel's Christian Democratic Union party.
Last week, the German chancellor rejected the idea that the Navalny case should be linked to Nord Stream 2, a project that has drawn the ire of the United States and some European partners.
In Washington, the U.S. National Security Council said the United States would work with allies "to hold those in Russia accountable, wherever the evidence leads, and restrict funds for their malign activities."
In Congress, lawmakers called on the Trump administration to impose congressionally mandated sanctions on Russia.
Navalny's poisoning has echoes with the case of former Russian double-agent Sergei Skripal and his daughter in the British city of Salisbury. A British investigation determined that the Skripals had been poisoned with Novichok and alleged that the attack was carried out by Russian state agents.
The British government expelled 23 Russian diplomats after Moscow refused to cooperate with an investigation into the Skripal poisoning. The United States and other European states expelled dozens of Russian diplomats in a coordinated response.
From the beginning, allies of Navalny have said that the Russian state was behind the poisoning, and the legal department of his Anti-Corruption Foundation has filed a complaint over what it called the Russian Investigative Committee's inaction in the case.
A Moscow court has dismissed the complaint, a decision lawyer Vyacheslav Gimadi said would be appealed.
Navalny, who has been attacked and arrested several times in the past, is a leading politician, anti-corruption campaigner, and protest leader.
He had been in Siberia for his latest investigation into corruption and to support opposition candidates in September’s local elections before he fell ill.
In a gesture of political support for Russia, Belarus's embattled President Alyaksandr Lukashenka, who is himself facing international condemnation over last month's presidential election and the ensuing crackdown on protesters, said on September 3 that Belarusian intelligence had eavesdropped on a phone call allegedly indicating that Navalny's poisoning was a "falsification."
Lukashenka alleged that the conversation involved people in Warsaw and Berlin whom he didn't name.
"There was no poisoning of Navalny," he said.
"Naturally, the claim made by Mr. Lukashenko is untrue," German government spokesperson Steffen Seibert said on September 4.