BRUSSELS, Germany (AP) — The European Union and Britain imposed sanctions Thursday on six Russians, some among the highest-ranked officials in the nation, and one organization over the poisoning of Russian opposition leader Alexei Navalny with a Soviet-era nerve agent.

Foreign Minister Heiko Maas of Germany, which holds the EU’s rotating presidency, said that “only with a clear position and by sticking to principles can we as the European Union make progress with respect to Russia.”

The sanctions consist of a travel ban to the EU and an asset freeze for individuals and the targeted organization, the EU said.

The list includes Alexander Bortnikov, the chief of Russia’s Federal Security Service, the top KGB successor agency that is in charge of domestic security, and Sergei Kiriyenko, Putin’s deputy chief of staff. The EU is also targeting the State Scientific Research Institute for Organic Chemistry and Technology.

The UK said it would also apply the EU sanctions and will continue them once it leaves a post-Brexit transition period at the end of the year.

“Any use of chemical weapons by the Russian state violates international law. We are determined to hold those responsible to account,” British Foreign Secretary Dominic Raab said.

Russian officials have repeatedly denied any involvement in the poisoning and Russian doctors who first examined Navalny have said they found no signs of a poisoning.

Kremlin spokesman Dmitry Peskov called the move “a deliberate unfriendly step towards Russia” and said that the EU “inflicted damage” on the bloc’s relations with Russia.

“Moscow will analyse the situation and will act in accordance with its own interests,” Peskov said, adding that “no logic can be seen in such a decision” by the EU.

EU foreign ministers agreed Monday to impose the sanctions, following a push by France and Germany to freeze the assets of those suspected of involvement in the poisoning and ban them from traveling in Europe under sanctions to combat the use and spread of chemical weapons.

The legal procedures were completed Thursday.

French Foreign Minister Jean-Yves Le Drian said the EU had acted “with exceptional speed, in keeping with the seriousness of this act and the methods used.”

“This demonstrates a European Union that acts in the face of the new, unacceptable and destabilizing use of a chemical weapon,” he said at a meeting in Paris.

Navalny, an anti-corruption investigator who is the most visible political opponent of Russian President Vladimir Putin, fell ill on August 20 during a domestic flight in Russia. He was flown to Germany for treatment two days later and is still recovering there.

Last week, tests conducted at labs designated by the Organization for the Prohibition of Chemical Weapons confirmed that Navalny was poisoned by a Novichok nerve agent. They confirmed results found earlier in labs in Germany and elsewhere.

Russian Foreign Minister Sergey Lavrov has suggested that Moscow might even sever ties over the Navalny dispute, claiming Wednesday that “the Germans are not planning to provide any facts, despite all international and legal obligations. We respond in kind. This is diplomatic practice.”

“We probably simply have to temporarily stop talking to those people in the West who are responsible for foreign policy and don’t understand the need for mutually respectful dialogue,” he said a day earlier.

Lavrov specifically pointed at European Commission President Ursula von der Leyen’s recent statements ruling out a partnership with Russia, saying that scenario will play out if that’s what the EU wants.

“Russia wants to understand whether it’s possible to do any business with the EU in the current conditions,” Lavrov said at a foreign policy conference attended by experts in Moscow.

In a phone call Tuesday with Lavrov, EU foreign policy chief Josep Borrell insisted that the EU “wishes to maintain open channels of communication with Russia and to enhance cooperation on issues of mutual interest,” according to a statement from Borrell’s office.

Borrell also underlined that Moscow “must do its utmost to investigate this crime thoroughly in full transparency and to fully cooperate” with the OPCW. He said the EU “will continue to defend its interests and values, including respect for international law and fundamental rights.”