Ahead of next month's elections to the European Parliament, France's far-right National Rally is boasting a star new recruit.

Until two years ago, Fabrice Leggeri was executive-director of the European Union's border agency Frontex.

For the National Rally (RN), already riding high in the opinion polls, the arrival of such an important figure is a major coup.

Mr Leggeri, 56, was schooled to be part of France's administrative elite.

Before taking over at Frontex in 2015, he held posts in the interior, defence and foreign ministries.

His establishment status helps push back against a persistent criticism of the RN, that it lacks the human talent needed for effective government.

The former high-ranking EU official, who still lives in Brussels, is scathing about the European Commission and the way he claims it allowed an NGO pro-migrant agenda to undermine his task of patrolling EU borders.

He also blames President Emmanuel Macron for failing to support him, when it was clear he was falling out of favour with the Commission.

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Founded in 2004 and based in Warsaw, the EU's Border and Coast Guard Agency is supposed to help member states enforce the zone's external frontiers. It has an annual budget of nearly €900m (£770m) and a staff set to rise to 10,000 by 2027.

But Fabrice Leggeri is not without controversy of his own. Critics say he resigned in 2022 after he was accused of colluding in "pushbacks" of migrants by Greek authorities into Turkish waters - which NGOs said were illegal.

Last week, French human rights groups filed a suit against him for complicity in crimes against humanity for his role in the "pushbacks", and for allegedly giving information to Libyan authorities that allowed them to stop boats entering European waters.

"There is a clear consistency between his thought and actions as head of Frontex and his political allegiance to the RN," said Patrick Baudouin of the League for Human Rights.