Ukrainians go to the polls this weekend to vote in a presidential election that has a result that is far from certain.

Russia will be keeping a close eye on the result to see how pro-western — or anti-Russian — Ukraine's next leader might be. It is the first national vote since Russia annexed Crimea in early 2014 and subsequently supported an uprising by pro-Russian separatists in east Ukraine.

The armed conflict in the eastern Donbass region has died down following numerous ceasefires that have been implemented and then collapsed. Attempts to stop the conflict were made in Minsk in late 2014 and again in 2015 (known as the Minsk Agreement) but both sides accuse each other of not complying with agreed conditions.

President Poroshenko's presidency has been dominated by relations with Russia and he has been closely watched for his responses to instances of Russian aggression towards, or provocations of, Ukraine – such as the incident in the Kerch Strait last November in which three Ukrainian Navy vessels were seized.

Ukraine's economic crisis and its 2015 $17.5 billion bailout (and recent $3.9 billion loan) from the International Monetary Fund, as well as its attempts to get closer to the European Union and NATO, have also dominated Poroshenko's tenure. These issues are bound to pressure the new president whoever wins the race.

In the closing days of campaigning before a first round of voting takes place on Sunday, actor and comedian Volodymyr Zelensky leads public opinion polls ahead of rivals Yulia Tymoshenko and incumbent Petro Poroshenko. If none of the candidates get more than 50 percent of the votes in the first round Sunday then a runoff will be held on April 21.