European Union ambitions to dramatically increase nuclear power are in need of an economic-reality check, according to financial-watchdog data which shows that a significant investment gap could put climate goals increasingly at risk.

According to a report by Brussels-based thinktank Finance Watch, the EU requires more than $250bn (€229bn) of the $5tn needed globally for nuclear technology.

Those levels of investment are poised to face financing hurdles that capital markets are unable to resolve, Finance Watch said. High EU debt, fiscal constraints and doubts about future electricity-market structure are combining to create a gulf in funding, according to the report’s author Thierry Philipponnat.