Dutch voters are heading to the polls, to decide whether to support a key EU deal with Ukraine, which mainly bolsters trade. 

The national referendum has been triggered by grassroots eurosceptic groups. It will be valid only if 30 percent of voters turn out. Opinion polls on the eve of the vote showed opinions greatly divided, and the "No" campaign having a slight edge. The vote is being anxiously watched in Ukraine, as the country seeks closer ties with the West since the 2014 unrest, which caused then President Viktor Yanukovich to step down. Over the past weeks, Kiev has sent top ministers to the Netherlands to help boost support for a "yes" vote.