Pivotal moment for EU as voters choose between unity and disruption

Senior research fellow Camino Mortera-Martinez from the Centre for European Reform (CER) argues that while those ascendant political groups may not dominate Parliament, their presence will be felt as they apply pressure and complicate EU decision-making.

"Euroskeptics and populists are going to grow exponentially this time," she says. "You're going to have a much more divided Parliament. It's going to be more difficult to find compromises."

Mortera-Martinez says there was always going to be a surge in populist parties following the migration crisis, eurozone woes and various terrorist attacks across the continent.

...However, Mortera-Martinez suggests that populists, nationalist and euroskeptic parties will ultimately struggle to work together "so their influence will diminish a lot because of the lack of coordination."