A string of attacks in Europe has pushed terrorism to the top of the table of concerns for EU nationals in 2017, according to a poll of more than 33,100 people across the 28-nation bloc.

The EU Commission's latest Eurobarometer, made up of face-to-face interviews between 20 and 30 May, was published on Wednesday 2 August.

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The findings follow, among other incidents, the Manchester Arena suicide bombing in May, the Notre Dame hammer attack in France in June and the foiled attack on the Russian embassy in Berlin, Germany, in April.

Terrorism is scored at 44% (+12 from autumn 2016) compared to immigration at 38% (-7), which had been a top concern since spring 2015.

The issues are well ahead of the economic situation at 18% (-2), the state of EU nations' public finances at 17% (unchanged) and unemployment at 15% (-1).

"Terrorism is the number one concern for the EU in 21 Member States, while this was the case in one country only in autumn 2016. Terrorism and immigration are mentioned as the top challenges in all countries except for Portugal and Sweden." the EU Commission noted.

The research also revealed that a majority of EU nationals or 56% (+6%) are optimistic about the future of the EU, just a year after the UK voted to split from the bloc at a referendum in June 2016. The most significant increases can be observed in France at 55% (+14) and Denmark at 70% (+13).

Trust in the EU continues to be on the rise and stands at 42% (+6). It has increased most strongly in France at 41% (+15 points), according to the latest Eurobarometer. The survey comes after the election of Emmanuel Macron over anti-EU populist Marine Le Pen.

Macron, the leader of the En Marche! movement, warned that the EU had "lost its way" in a speech to the French parliament in July. 'The building of Europe has been weakened by the spread of bureaucracy and by the growing scepticism that comes from that," he said.

European Union