Voting is taking place in eastern Ukraine in a disputed independence referendum amid reports of chaotic scenes.
A severe shortage of polling booths, ballot papers being printed off unsupervised, and confusion over what people are actually being asked to vote on, are reported to have beset the hastily-organised vote in Donetsk and Luhansk provinces.
The referendum has been held in defiance of Moscow by pro-Russian militants and polls close at 8pm UK time.
People queue up to vote on the future of Donetsk and Luhansk regionsMore than three million ballot papers have been distributed across the regions, with organisers claiming to have spent just £980 on the entire ballot.
While voting has so far has been largely peaceful, in Mariupol - the scene of fierce fighting in recent days - there were just eight polling stations for half a million people.
It has led to lengthy queues, and at one centre, ballot boxes were put out on the pavement.
The vote has been declared illegal by both the Kiev government and the international community and marks a serious deepening of the political crisis in Ukraine.
Acting chief of the Ukrainian presidential administration Sergiy Pashinski said: "The turnout throughout the whole region amounts to zero as far as formalities are concerned.
"I would like to underline one more time it's not a referendum. It is a desultory attempt by terrorists, bandits and killers to cover their activity by having citizens vote in Luhansk and Donetsk."
Angela Merkel and Francois Hollande want a reduction of Russian troopsAlthough a 'yes' vote would likely only be recognised by Russia, it would greatly undermine a presidential election that Ukraine is to hold in two weeks, which the US and Europe see as crucial to restoring stability.
A Foreign Office spokesman said: "It is regrettable that separatists who are causing so much disruption to the lives of ordinary citizens are going ahead with their illegitimate, so-called referendum today.
"All Ukrainians will have a proper opportunity to express their democratic choice in the forthcoming presidential elections on May 25.
"The focus must be on ensuring that free and fair elections can go ahead in a calm and stable environment."
It came as France and Germany called on Russia to prove it had withdrawn its forces from the Ukrainian border.
A pro-Russian at a checkpoint near SlavyanskGerman Chancellor Angela Merkel and French President Francois Hollande issued a joint statement saying there needed to be a "visible" reduction in troops close to the crisis-hit country.
Earlier this week, Russian President Vladimir Putin said his country's forces had moved back to training bases, although the White House and Nato both said they had seen no movement.
The joint statement, issued after a meeting in Stralsund, Germany, also called on Ukrainian security forces to "abstain from taking offensive actions" before the start of presidential elections.
Mrs Merkel said Mr Putin "must send more signals of de-escalation" so the May 25 poll can go ahead.
The vote comes amid intensifying violence on the ground in east Ukraine.
Troops have been battling the well-armed rebels, who have barricaded themselves in towns and cities in Donetsk and Luhansk.