The founder and CEO of the Formula E championship Alejandro Agag has predicted that the all-electric series will be the last motor racing championship standing in 20 years' time.

Agag said that with the real-world decline of traditional engine technology and fossil fuels, electric cars would soon dominate the sport.

"I think Formula E is going to get really, really big," Agag predicted. "I believe that in 20, 30, 40 years, we will be the only motorsport out there."

Agag was talking to ESPN on Wednesday at an event in London announcing the signing of ABB as Formula E's title sponsor. The deal is believed to be worth in the region of $15 million per year, and expected to last through to 2025.

"There may be others but we will be probably the main motorsport because the world will be electric," Agag continued. "If the world is not electric in 20 or 30 years, we are in trouble.

"Even if that happens, then Formula E will be the championship of the cars."

Agag was reminded of Sir Richard Branson's prediction in 2015 that Formula E could surpass Formula 1 as the top motorsport series by the end of the decade. Branson - himself a former F1 team owner - now operates the DS Virgin squad in Formula E.

"I never disagree with Richard Branson," Agag replied. "He's a very clever man and he gets it right most of the time.

"[But] we never like to put ourselves in competition with Formula 1," he added diplomatically. "We love Formula 1, we think Formula 1 is great."

Despite the modesty, Agag couldn't hide his delight at the leap in Formula E's fortunes during the last 12 months.

As well as the lucrative title rights deal, Formula E has also seen confirmation that Porsche and Mercedes will join the series as manufacturers alongside Renault, Audi and Jaguar Land Rover.

Formula E has also successfully developed partnerships with Visa, Swiss bank Julius Baer, and German insurance company Allianz. Fashion giant Hugo Boss also recently ended its long-time association with F1 in favour of a switch to Formula E.

"We are far beyond our expectations from when we launched the project," Agag said. "I have been surprised.

"The title sponsorship" is another huge step. We wouldn't have imagined this when we started the project.

"We keep getting good surprises, so I think that probably means that we are moving in the right direction."

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