The Spaniard will quit Formula One at the end of this season and is likely to make the switch to racing in IndyCar.
However, Formula E CEO Agag said he has spoken to the two-time F1 champion about joining the series in 2020.
'I've been speaking with Fernando. Actually, I was with him in Monza,' he told the South China Morning Post.
'I think he's going to America this season, but definitely for the season after we are going after him.
'I speak with Fernando a lot, he likes Formula E a lot. He's very car-focused, Fernando.
'He's very curious about the new car that we are starting in season five. He wants to know more about that car and he think it looks very cool. Fernando is all about the car.'
Alonso's former Ferrari teammate, Felipe Massa, has joined Formula E for its fifth season, which starts later this year.
And Agag is optimistic that with the Brazilian's arrival it will continue to help the series to grow.
'Massa is a great driver, he's a great friend, he's a really cool personality, and he has a big following all around the world,' Agag said.
'For him to drive in Formula E, it's great for the championship. We have a great line-up of drivers, second only to Formula One.
'Apart from that we are probably the best in the world. More drivers are doing fully Formula E, because of the growth — there are bigger budgets to pay the salaries so the drivers are exclusive.
'Formula E is becoming the priority.'
Alonso is set to make a decision on his 2019 season in October.
Raikkonen leaves Ferrari0:25
F1: F1 veteran Kimi Raikkonen will leave Ferrari for former team, Sauber for the 2019 season.
September 12th 2018
3 days ago
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This story first appeared in The Sun and was republished with permission.