Since its takeover of F1 in 2017, Liberty Media has been eager to grow the series in the United States, with plans for a grand prix in Miami being worked on over the past two years.

Opposition has led to a number of changes to the proposals. The current plan sees the circuit avoid public roads around the Miami Dolphins’ Hard Rock Stadium, as well as avoiding on-track action during school hours.

The project is still facing protests from a number of local groups, most notably at the Super Bowl, which was held in Miami at the start of February.

But a major victory was scored earlier this month when commissioners did not vote down the proposals, allowing the Miami Dolphins’ owners to proceed with plans to build the circuit within its grounds.

Speaking to Motorsport.com at the BHMSE conference in Baku, F1 CEO and chairman Carey conceded he felt some frustration over the delays, but said building the series’ profile in the United States has always been viewed as a long-term project.

“We knew the US was going to take time. On one level, yes, it is clearly taking longer than we would have hoped,” Carey said.

“I think it’s frustrating on one level because we’ve spent as much time and there seems to be always some degree of ongoing complexity.

“I think the reality is that the US for us, to really build it, it’s a five-year-plus timeframe. We said all along the US isn’t going to change our world in two to three years.

“The goal is really in five to 10 years from now, the US becomes a meaningful market for us. In that context, 12 months it isn’t that big a deal, but that doesn’t mean it’s not frustrating as you continue to go through it.”

Talk of additional F1 races in the United States has intensified following Roger Penske’s purchase of Indianapolis Motor Speedway.

Penske confirmed at the time of the acquisition he would assess the possibility of bringing F1 back to Indianapolis, which hosted the United States Grand Prix between 2000 and 2007.

Carey remained coy on any talks with Penske, but said he was aware of the interest and spoke warmly of the circuit’s place within global motorsport.

“I know the Penskes, I’ve had contact with the Penskes, I knew them before they bought Indianapolis,” Carey said.

“But again I probably wouldn’t comment on conversations. I’m aware of the interest.

“It’s obviously an iconic track for world racing. It’s part of the Triple Crown, Monaco, Le Mans and Indy, so it speaks to what that track means. It’s a special track for the motorsports world.”