Ukraine and Russia will attempt fresh talks this morning, ahead of a Russian deadline for Kiev to pay a $1.95 billion (£1.15 billion) debt or have its gas supplies cut off.
The two countries failed to end a gas pricing dispute at talks yesterday.
Russia's decision to stop deliveries to Kiev could disrupt the gas flow to the European Union, which receives its energy via Ukraine.
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The annual event has earned a place in the record books ahead of the grand final of the 60th anniversary show in Austria this evening.
Local authorities said the move is necessary to "avert the growing number of deaths and increasing harm linked to psychoactive substances".
Some students argued that the centuries-old tradition of wearing gowns, suits and mortarboards to exams was 'archaic' and looked elitist.