Charles Leclerc's rise meant the writing was on the wall for Vettel

The writing has been on the wall for Sebastian Vettel since September 2018 when Ferrari announced Charles Leclerc as his Formula One team mate.

The German, who will leave the Italian team at the end of a pandemic-hit 2020 season that has yet to start, was top dog at Maranello at the time but Leclerc was young, hungry and determined.

Strapped into the red car for 2019, the Monegasque — now 22 — outperformed the four-time world champion on just about every measurement.

He won more races (2-1), scored more points (264-240), started from more poles (7-2), stood on more podiums (10-9), had more fastest laps (4-2) and drew more applause than his 32-year-old team mate whose status as the main man slipped out of sight.

By the end of the year, Leclerc had a new contract taking him through to the end of 2024 and was clearly the face of the future.

Vettel, who arrived at Maranello from Red Bull in 2015 as the replacement for Spaniard Fernando Alonso, is paid a reported annual salary of $40m (roughly R734.3m).

In return he has taken 14 wins over the past five years, only one more than in his final 2013 season at Red Bull, to take his career tally to 53.

The German had hoped to emulate Michael Schumacher, a boyhood hero who won five of his seven titles with the sport's oldest and most successful team, but the closest he came was second overall in 2017 and 2018.

In 2016 he was fourth overall, without a win, and last year he finished fifth, further away than ever to bringing Ferrari their first drivers' title since Kimi Raikkonen in 2007.

Mercedes' Lewis Hamilton has accelerated past him and is now a six-time champion on the cusp of matching Schumacher's record.

Vettel has seemed ill at ease in the car, making costly errors both forced and unforced. Some have questioned his motivation and wondered about retirement.

That pressure and frustration was evident in Canada last year when a time penalty dropped him from first to second and he angrily replaced the number one sign positioned post-race in front of Hamilton's car with the number two.

At Monza last year, with Leclerc on his way to winning Ferrari's home race from pole position, Vettel spun off and then nearly took out Lance Stroll's Racing Point as he returned clumsily on track.

In Brazil, the two Ferrari drivers collided and retired from the race.

“In order to get the best possible results in this sport, it's vital for all parties to work in perfect harmony,” Vettel said on Tuesday.

“The team and I have realised that there is no longer a common desire to stay together beyond the end of this season.

“My immediate goal is to finish my long stint with Ferrari, in the hope of sharing some more beautiful moments together, to add to all those we have enjoyed so far.”