10 May 2012 Last updated at 05:10 ET

Ukraine profile

Ukraine gained independence after the collapse of the Soviet Union in 1991 and has since veered between seeking closer integration with Western Europe and reconciliation with Russia, which supplies most of the country's energy.

Europe's second largest country, Ukraine is a land of wide, fertile agricultural plains, with large pockets of heavy industry in the east.

While Ukraine and Russia share common historical origins, the west of the country has close ties with its European neighbours, particularly Poland, and Ukrainian nationalist sentiment is strongest there.

A significant minority of the population of Ukraine are Russians or use Russian as their first language. Russian influence is particularly strong in the industrialised east, as well as in Crimea, an autonomous republic on the Black Sea which was part of Russia until 1954. The Russian Black Sea Fleet is based there.

Crimea is also the homeland of the Crimean Tatars whom Stalin accused of collaborating with the Nazis and deported to Central Asia in 1944. More than 250,000 have returned since the late 1980s.

In 1932-1933 Stalin's programme of enforced agricultural collectivisation brought famine and death to millions in Ukraine, the bread basket of the USSR. Not until its twilight years did the Soviet Union acknowledge the extent of the suffering.

News of another Soviet-era calamity, the 1986 accident at the Chernobyl nuclear power station, rang alarm bells around the world immediately. About 8% of Ukraine's territory was contaminated as were large areas in neighbouring Belarus. Millions have suffered as a result.

Independence

The first president after independence, former Communist Party official Leonid Kravchuk, presided over a period of economic decline and runaway inflation. His successor, Leonid Kuchma, oversaw steady economic recovery, but was accused of conceding too much to Russian economic interests.

Opposition to Mr Kuchma grew, further fed by discontent at controls on media freedom, manipulation of the political system and cronyism.

The authorities' attempt to rig the 2004 presidential elections led to the "Orange Revolution", with reference to the colour of the main opposition movement.

Orange Revolution

Mass protests, a revolt by state media against government controls and the fracturing of the governing coalition brought in European-Union mediation and a re-run of the election.

A fragile alliance of anti-Kuchma forces, from pro-Western democrats, socialists, business interests and nationalists united behind opposition leader and former prime minister Viktor Yushchenko, who won the presidency.

Mr Yushchenko secured the transparency of the democratic process, the rule of law and media freedom, but his efforts to move towards Nato and EU membership made slow progress in the face of Western reluctance to antagonise a resurgent Russia and a divided public opinion in Ukraine itself.

Rivalry with his prime minister, Yuliya Tymoshenko, soured into open antagonism, and neither proved able to cope with the worldwide economic downturn after 2008.

Their opponent in the 2004-2005 Orange Revolution, Viktor Yanukovych, won the 2010 presidential election. He swiftly re-oriented foreign and trade policy towards Russia and clamped down on media freedom. He also had various oppenents, most prominently Ms Tymoshenko, imprisoned in trials regarded at home and abroad as politically-motivated.

Although trade with EU countries now exceeds that with Russia, Moscow is the largest individual trading partner. Ukraine depends on Russia for its gas supplies and forms an important part of the pipeline transit route for Russian gas exports to Europe.

Gas disputes

A dispute over price rises prompted Russia briefly to cut supplies for use by Ukraine in January 2006 and raised concerns across Europe too. The gas was switched back on only after Ukraine agreed to pay almost twice the former price, which rose sharply again for 2007. In January 2009, Russia again cut gas supplies in a row over unpaid fees.

The Ukrainian economy's dependence on steel exports made it particularly vulnerable to the effects of the global financial crisis of 2008, and in October of that year the country was offered a $16.5bn (£10.4bn) loan by the International Monetary Fund (IMF).