Russia has shown, as recently as 2014, that it is not averse to taking military action in Ukraine. In that year, Russia seized Crimea from Ukraine in what was the first time a European country annexed territory from another country since World War Two.

What are Russia’s and the West’s interests in Ukraine?

Ukraine and Russia share hundreds of years of cultural, linguistic and familial links. As part of the Soviet Union, Ukraine was the second-most powerful Soviet republic after Russia, and was crucial strategically, economically and culturally. Ever since Ukraine split from the Soviet Union, both Russia and the West have vied for greater influence in the country in order to keep the balance of power in the region in their favour.

For many in Russia and in the ethically Russian parts of Ukraine, the shared heritage of the countries is an emotional issue that has been exploited for electoral and military purposes.

For the United States and the European Union, Ukraine is a crucial buffer between Russia and the West. As tensions with Russia rise, the US and the EU are increasingly determined to keep Ukraine away from Russian control.

Efforts to induct Ukraine into NATO have been ongoing for many years and seems to have picked up pace recently. Russia has declared such a move a “red line”, with Moscow worried about the consequences of the US-led military alliances expanding right up to its doorstep.

What was Euromaidan and its aftermath?

November 2013 saw the start of mass protests across Ukraine, but particularly in Kyiv’s Maidan, or central square. Protesters were angry at Ukraine’s then pro-Russia President Viktor Yanukovych’s decision to join the Russia-led Eurasian Economic Union instead of the EU. The protests, known as the Euromaidan movement, saw massive clashes between the protesters and security forces that reached its peak in February 2014, and led to the ouster of Yanukovych.

Soon after, amid fears of growing Western influence in Ukraine, Russia decided to take action by invading Crimea, which was a part of Ukraine. Moscow also began fomenting a separatist movement in eastern Ukraine, which is home to many who are ethnically Russian.

The invasion and subsequent annexation of Crimea have given Russia a maritime upperhand in the region. It also gave President Vladimir Putin a significant boost in popularity ratings inside Russia. However, it was widely condemned by world powers, and resulted in the US and EU imposing sanctions on Moscow. It also resulted in a strengthened commitment by both the US and the EU to protect the integrity of Ukraine’s borders.

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What is happening now?

As it moves a large number of troops towards the border, Russia seeks assurances from the US that Ukraine will not be inducted into NATO.

However, US President Joe Biden has made it clear that he is not prepared to give any such assurance. This has left the countries in a stand-off, with tens of thousands of Russian troops ready to invade Ukraine at short notice, and the West not budging on Russia’s demands.

Putin and Biden are set to talk via video link on Tuesday, and many experts believe that Russia is keeping the tensions high at the Ukraine border in order to get sanctions relief and other concessions from the West. Frantic diplomatic efforts, involving US, European, Ukrainian and Russian officials, are underway to avoid military action.

What next?

US officials, including Defence Secretary Lloyd Austin, have admitted that they are not sure what Putin’s intentions are. If the diplomatic efforts to stop the invasion fail, US and EU officials have said they may impose hard-hitting sanctions on Russia in the event of military action on the Ukraine border.

However, depending on what Putin’s intentions are, experts say sanctions may not be enough to deter him. Any kind of military action by the US or EU against Russia would precipitate a major crisis for the whole world, and has so far not been mooted by any of the parties involved.