The announcement will see McLaren's stake in the two-car squad increased to 75 percent by year's end.
“Today's announcement is a strong signal of our long-term commitment to IndyCar as both a racing series and a marketing platform for McLaren Racing and our sponsor partners,” said McLaren Racing CEO Zak Brown.
“I want to pay tribute to Sam Schmidt and Ric Peterson who, together with the commitment and support of Arrow Electronics, have built a formidable team for us to keep growing and fulfil our common ambition of consistently challenging for wins, Indy 500s and series titles.
“Key to this is the continued leadership of Taylor Kiel as president of the team, who has been instrumental to the progress of the partnership so far.
“McLaren Racing believes IndyCar will continue to build our brand in North America, serve our expanding US fan and partner base across our racing portfolio and drive long-term value.
“The racing is second to none, with world-class competitors in both drivers and teams and a passionate, highly engaged fanbase.
“We see real potential for the series' continued growth under the stewardship of Penske Entertainment and will continue to play an active role supporting the sport's success, growing the global fan base and implementing our sustainability agenda to deliver on environmental and social commitments, including progressing diversity and inclusion in the industry.”
Foundation owner Schmidt added: “I've known Zak for 25 years. He's a racer, and this is a group of hardcore racers.
“We started our partnership two years ago and it's gone extremely well, both technically and commercially.
“Ric came in 2013 and moved the bar of the team up. Arrow came in a couple of years later and again we moved the bar up.
“With McLaren, we're moving forward again. As we've seen, we're now a regular contender and ultimately for Ric and I, we are here to win races, win 500s and win championships.
“This next step ensures the resources to do that for a long time ahead.”
Peterson similarly voiced his excitement: “We always believed that to accelerate our progress in IndyCar, partnering with a team of McLaren's capability and F1 experience was a key strategy to propel us forward, and so it has proved.
“McLaren Racing now takes the baton and will combine the best of what they do with the best of what this team does to create something truly special.
“Sam and I are immensely proud of what we have built together through our partnership over the past nine years, and look forward to continue being part of this team as a partner with McLaren Racing to see Arrow McLaren SP go from strength to strength.”
McLaren SP runs Pato O'Ward and Felix Rosenqvist in IndyCar, both of whom are believed to be under contract for 2022.