The UK and the US have both threatened to sanction Russian president Vladimir Putin personally if he chooses to invade Ukraine.
This comes as the presence of more than 100,000 Russian troops at the Ukrainian border has brought the spectre of war to Europe.
While the west sends arms to Ukraine in preparation for a potential conflict, it continues to attempt to deter Russia from a military incursion through the threat of economic sanctions. Moscow denies that it wants to attack its neighbour - like it did in 2014 in Crimea - but stresses it can move troops as it pleases inside its territory.
Diplomatic talks between officials from Russia, Ukraine, France and Germany are due to take place in Paris on Wednesday.
US president Joe Biden said on Tuesday that a Russian invasion could lead to sanctions against Mr Putin himself. America rarely takes such action against leaders of other countries, although exceptions include those levelled against Venezuela’s Nicolas Maduro and Syria’s Bashar al-Assad in recent years.
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The Kremlin struck out against the suggestion on Wednesday, saying the west does not enough “expert knowledge” on the subject.
A spokesman said that any move to sanction the Russian leader would prove politically destructive but not painful.
The prospect of sanctioning the Russian president was also raised by the British government this week, with foreign secretary Liz Truss saying ministers were “not ruling anything out”.
"We’ll be bringing forward new legislation to make our sanctions regime tougher so we are able to target more companies and individuals in Russia. We will be bringing that forward in the next few days,” she added.
Meanwhile, Boris Johnson said on Tuesday that western unity was vital “in deterring any Russian aggression”. Speaking in the Commons, the prime minister hinted that Russia could be banned from the Swift global payments system as part of a suite of economic measures.
Although both the UK and US have made it known that they will not send troops to help Ukraine, which is not a member of Nato, they have sent military hardware to their ally.
Ms Truss said the UK was providing defensive weapons to Kyiv, while a third US shipment of military equipment landed in Ukraine on Tuesday. This comes as part of a $200 million (￡148m) US support package. A total of 8,500 US troops could be deployed to NATO’s eastern flank if it is deemed necessary.
If Russian troops strike out into Ukraine, it would constitute “the largest invasion since World War II” and “would change the world”, Mr Biden warned.
For its part, Ukraine emphasised its commitment to a diplomatic solution to ease tensions. The country’s president Volodymyr Zelensky has sought to calm the Ukrainian public, while his foreign minister said Russia has not amassed enough troops for a full-scale invasion.
"There are no rose-colored glasses, no childish illusions, everything is not simple… But there is hope," Mr Zelensky said. "Protect your body from viruses, your brain from lies, your heart from panic."
Elsewhere, Sergiy Korsunsky, the Ukrainian ambassador to Japan, suggested there was little chance of a full offensive, warning Moscow of the dangers of invading a country with 15 nuclear reactors. "I believe that full-scale war is very, very, very difficult to expect, but we may see more localised conflict," he said.
On Wednesday, Alexey Pavlovsky, the Russian ambassador to Australia, claimed that the Kremlin did not want to launch an incursion.
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"Our troops on the border...These troops are not a threat, they are a warning. A warning to Ukraine’s rulers not to attempt any reckless military adventure," he said.
Additional reporting by Reuters