Perceiving the CIS as an attempt to bring ex-Soviet republics under Moscow's control, it takes a lukewarm approach to the structure and turns towards the West. It seeks ties with the US-led NATO military alliance -- a no-go for Russia.

In the aftermath of the end of the Cold War, Ukraine, Russia, the UK and the US in December 1994 agree to respect the independence, sovereignty and borders of Ukraine. The agreement is in exchange for Ukraine abandoning the nuclear weapons it inherited from the Soviet Union.

Friendship Treaty

In May 1997 Russia and Ukraine sign a friendship treaty without removing a main source of tension: Kiev's ties with NATO.

It settles a key disagreement by allowing Russia to retain ownership of the majority of ships in the Black Sea fleet based in Ukraine's Crimea while requiring that Moscow pay Kyiv a modest rent to use the port of Sebastopol.

Moscow also remains Kyiv's most important commercial partner, with Ukraine totally dependent on Russian oil and gas.

Ukraine draws a warning from the EU in 2003 when it signs an accord with Russia, Belarus and Kazakhstan on a Common Economic Space. Brussels says that it could hinder Ukraine's rapprochement with the bloc and its membership to the World Trade Organization.

Pro-Westerner In Power

Ukraine's 2004 presidential election is marred by fraud and the victory of the pro-Russian Viktor Yanukovych provokes unprecedented protests in the peaceful Orange Revolution.

The uproar leads to the vote being cancelled and in December pro-Western opposition leader Viktor Yushchenko, who was victim of a mysterious dioxin poisoning during the campaign, becomes president.

It marks the beginning of a new political era in Ukraine after 10 years under the thumb of Leonid Kuchma, who staggered between Europe and Moscow.

Yuschenko swiftly reiterates Ukraine's wish to join the EU, despite reservations from the bloc, along with NATO.

In 2008 at a summit in Bucharest, NATO leaders agree that Ukraine has a future in the alliance, sparking Moscow's ire.

Russia and Ukraine engage in several disputes, notably over gas in 2006 and 2009 which disrupt Europe's energy supplies.

Pro-European Uprising

Yanukovych is elected president in 2010, and in November 2013 he suspends talks on a trade pact with the EU in favour of closer ties with Russia.

It sparks weeks of massive protests by pro-European opposition groups demanding the pro-Russian president quits.

The uprising, centred on Kiev's Independence Square, comes to a head in February 2014 when police fire on protesters.

Around 100 demonstrators and 20 police officers die during the three-month uprising.

Yanukovych flees to Russia and is impeached.

Annexation And War

Russia responds by sending special forces to take control of strategic sites on Ukraine's Crimea peninsula.

In March 2014 Russian President Vladimir Putin signs a treaty absorbing Crimea into Russia.

The annexation provokes the worst diplomatic crisis between the West and Russia since the fall of the Soviet Union.

Then in April, a pro-Russian rebellion erupts in Ukraine's industrial eastern areas.

Pro-Russian separatists in Donetsk and Lugansk declare their regions to be independent.

Ukraine and its Western allies accuse Russia of instigating the uprising and pouring in arms and troops to bolster the self-proclaimed republics.

The clashes become a full-blown conflict in May and the conflict has since left more than 14,000 people dead.

After massing tens of thousands of soldiers on Ukraine's borders, Putin on February 21, 2022 recognises the independence of Donetsk and Lugansk.

He also orders Russian troops into the regions, without giving the scope or timetable of the deployment.