Two days before voting begins in European parliamentary elections, national leaders are scrambling to mobilise their supporters to resist a populist challenge.
European governments fear a good showing for eurosceptics in the vote, which begins on Thursday and runs to Sunday, will disrupt Brussels decision-making.
Opinion polls predict a significant advance for nationalist and populist forces opposed to closer European Union integration and threatening mainstream reform efforts.
French President Emmanuel Macron called the vote the most important European parliamentary election since the first in 1979 and warned the EU faces "an existential threat".
Turnout has fallen in each EU vote since 1979, and mainstream leaders hope Britain's Brexit spectacle and a scandal for the Austrian far-right will mobilise voters.