Zak Brown thinks McLaren will have to wait until 2022 to get a shot at catching top teams Mercedes, Ferrari and Red Bull.

The Woking based team was the most improved in 2019, beating Renault to fourth in the constructors' world championship.

McLaren supremo Brown says the team will have the same budget in 2020 with "an aggressive approach".

But while the top teams will be able to run joint development programs next year for the 2020 and 2021 cars outside of the budget cap, others like McLaren and Renault are likely to focus primarily on 2021.

Then, from 2021 with the new rules in place, the top teams will be limited to just $175 million budgets when preparing for 2022.

"The top teams will have to cut back their annual budgets and staff, which will be difficult for them," Brown told Auto Motor und Sport.

"We believe in our opportunity from 2022 and beyond."

Renault reserve driver Sergey Sirotkin also worked with a similar role at the similarly-powered McLaren in 2019, and he was impressed with what he saw.

"I saw McLaren from the inside and it was very impressive compared to the other Formula 1 teams I have worked with," he told Russia's Izvestia news agency.

"I think next year they will finish on the podium more than once."