Marcelo Bielsa’s side have ended their 16-year exile from the English top-flight after clinching promotion as Championship winners.
But Radrizzani is not satisfied with that and wants to ensure Leeds can hold their own among England’s elite clubs.
He is already working on plans to ensure Leeds’ stay in the top-flight is not a short one
Radrizzani confirmed initial investment would come from his holding company Aser.
“We have enjoyed fantastic success. But we’ve done it in a particular year and the impact of COVID-19 is also hitting the club financially,” he said.
“So we will need additional investment to be competitive and to continue our project and our growth and to maintain our position in the Premier League. We will need to add on I think.
“People have said I would sell in the Premier League, but I have always said I would sell probably if I couldn’t achieve the Premier League.
“But in this case I would love to stay 10 years, maybe more, 20, I’m still young. I don’t have any rush. I’m enjoying it.”
The Italian also expects the NFL’s San Francisco 49ers — 10 per cent stakeholders in Leeds — to increase their involvement in the club.
The 49ers reached the Super Bowl last season and are one of the most successful teams in NFL history.
“The 49ers have done a good deal investing in the club with me because they see their investment already worth probably 3.5 times higher in terms of value of what they put in,” Radrizzani said.
“They are obviously good friends, a good partner and I think they could bring more value in the management of the club in the Premier League than what has been done until now.
“I expect them to help us more, step up and potentially in the future years in the Premier League in club management, particularly the stadium and merchandise.”
Radrizzani said there are no current plans for Qatar Sports Investments, the owners of Paris St Germain, to invest in the club, but he did not rule it out in the future.
“We have a very good friendship,” he said. “We have been talking, but to be honest we haven’t reached any concrete point of any negotiation.
“But we are really good friends and if they want seriously to come, they can always find my door open for a discussion, but at this moment there’s nothing.”
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