THE Kremlin has slammed Britain’s raft of ‘insane’ punitive measures against Russia over the poisoning of a former double agent, warning they will respond to the sanctions.

Russia’s Foreign Minister Sergey Lavrov said that Moscow would soon retaliate to Britain’s decision to expel 23 Russian diplomats over the poisoning of a former Russian spy.

Lavrov said that Russia will “certainly” expel British diplomats.

He said that the move would come “soon,” but added Moscow would inform London via official channels before publicly announcing its countermeasures.

Lavrov said British accusations of Moscow’s involvement in the poisoning of Sergei Skripal and his daughter are intended to distract public attention from Britain’s troubled exit from the European Union.

He argued that “boorish and unfounded” accusations against Russia “reflect the hopeless situation the British government has found itself in when it can’t meet the obligations given to the public in connection with exit from the EU.”

The Russian Foreign Ministry’s spokeswoman said the accusations of Moscow’s involvement in the poisoning of an ex-spy had been driven by domestic policy factors in Britain.

Maria Zakharova said Thursday British Prime Minister Theresa May apparently was “aiming to posture as a strong leader” by blaming Moscow for the poisoning of Sergei Skripal and his daughter.

Britain on Wednesday announced the expulsion of 23 Russian diplomats, the severing of high-level contacts with Moscow and other measures.

Moscow said it would retaliate, but hasn’t yet announced its official response.

Zakharova said that Moscow expects Britain to produce evidence to back up its claims of Russian involvement, which she denounced as “unbelievable nonsense.”

She insisted that Russia has “no motive whatsoever” to poison Skripal and denounced U.S. support for the British claims as a reflection of “Russophobia.”

British Foreign Secretary Boris Johnson said Russia targeted a former spy with a military grade nerve agent to make it clear that those who defy the Russian state deserve to “choke on their own 30 pieces of silver.”

Johnson told the BBC on Thursday there was a message in the “smug, sarcastic response” from Moscow after the attack on Sergei Skripal and his daughter.

Johnson said the Russians “want simultaneously to deny it and yet at the same time to glory in it. The reason they’ve chosen this nerve agent is to show that it’s Russia, and to show people in their agencies who might think of defecting or of supporting another way of life, of believing in an alternative set of values, that Russia will take revenge.”

French President Emmanuel Macron expressed his solidarity with Britain after the poisoning of an ex-spy, as well as Australia’s High Commissioner to the United Kingdom Alexander Downer.

Earlier, Foreign Affairs Minister Julie Bishop said Australia would consider imposing harsher sanctions on Russia over its apparent involvement in the nerve agent attack.

She declared Russia “has an explanation that it must give” over the attack after speaking with her UK counterpart Boris Johnson overnight.

Australia already has sanctions on Russia, after its breach of Ukraine sovereignty and its annexation of Crimea, but Ms Bishop said the government would consider a further response once the investigation into the attack was complete.

“We support, in the strongest possible terms, the full investigation by the British authorities of this nerve gas attack,” she told reporters in Sydney.

Sergei Skripal and his daughter Yulia were attacked with a military-grade nerve agent known as Novichok, first developed by the then-Soviet Union in the 1970s.