"Following seven months of intense work I can confirm my participation in World Series by Renault," said Regalia, whose CV also includes campaigns in Auto GP, European F3 Open and Italian F3.
"It is another season racing in Europe and it's fantastic to join such a Formula 1 feeder series with Zeta Corse.
"It is an opportunity, and we must do everything in our power to seize it, because drivers such as [Sebastien] Vettel, [Daniel] Ricciardo, [Jaime] Alguersuari and now Carlos Sainz Jr, who was a rival in GP3 two years ago, [have graduated to Formula 1 from this series'] historic roll of honour."
Regalia will travel to Valencia, where the Russian-owned team is based, on Monday, ahead of the first pre-season test at Jerez on March 5-6.
"This is a completely new experience for me, so I need to make the most of pre-season tests," he said. "2015 is going to be a very important year for me, it's surely a crucial one."
Zeta Corse staged a title attack in the second half of the 2014 FR3.5 series thanks to the efforts of Roberto Merhi. The team has yet to announce its second driver for this season.
2015 FR3.5 line-up so far
DAMS Nyck de Vries, Dean Stoneman
Fortec Motorsports Oliver Rowland, TBA
Arden Motorsport Egor Orudzhev, Nicholas Latifi
Zeta Corse Facu Regalia, TBA
Lotus Meindert van Buuren, Matthieu Vaxiviere
Strakka Racing Gustav Malja, Tio Ellinas
AVF Beitske Visser, Alfonso Celis
Tech 1 Racing Aurelien Panis, Roy Nissany
International Draco Racing Pietro Fantin, Bruno Bonifacio
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