McLaren CEO Zak Brown has hinted the Monaco Grand Prix is among five Formula 1 races that fall short of "spectacular".

With F1 needing to make space to accommodate new races, the historic event on the streets of Monte Carlo, which was considered untouchable for many years, is now under pressure to prove it still deserves a place on the calendar.

The main reason for this is that other races have started to match the glitz and glamour Monaco is known for while also providing a better racing spectacle on Sunday, as bigger cars make overtaking almost impossible on the narrow circuit.

"There are a lot of great events on the Formula 1 calendar now - Singapore, Miami, Silverstone," McLaren chief Brown said, as quoted by GPFans.

Also Read:

• F1 drivers defend 'iconic', 'special' Monaco despite processional race
• Monaco GP 'guaranteed' beyond 2022, organiser claims
• Brawn defends Monaco: It can't be judged like the rest

"They all have different brands and how they put on events because what works in America is different to the UK and Singapore etc.

“So I think we’re fortunate that we have 23 fantastic Grands Prix, probably 18 that are spectacular, five that need to be worked on.

“Monaco is definitely a crown jewel. It has been around for a super-long time. They have always had a very favourable commercial deal," he noted.

"I think what Formula 1 is looking to do is to get them more in line, understanding and respecting what they bring to the table, but also to catch up to where the commercial realities of Formula 1 are today.”

Monaco is far from the only historic race also facing an uncertain future, with the Belgian GP at Spa-Francorchamps also potentially losing its place.

However, Brown believes the best way to balance the schedule is to rotate races on a two or three-year basis.

“Stefano [Domenicali, F1 CEO] has said he has got demand for up to 30 Grands Prix which we obviously wouldn’t be able to do.

“The maximum number of Grands Prix is 24 under the Concorde Agreement, we are in favour of trying to accommodate as many great countries and cities that want to host races but also look to go to some sort of rotational system.

“So you’re running 20 to 23 races a year but maybe you have 28 markets and so you have 16-17 core races and 10 that rotate every two years.

“The Olympics and the World Cup are every four, so an every-other-year scenario for some Grands Prix would maintain the levels of interest in them and would allow us to expand the markets we’re in without expanding the race calendar itself.

“We all believe we’re at capacity.”