Toto Wolff has revealed that he knew Lewis Hamilton was going to join Ferrari when Carlos Sainz phoned him several weeks before the move was officially confirmed.

In February, it was announced that Hamilton had signed a multi-year deal with Ferrari starting in 2025. He will replace Sainz, who has already secured his own future on the grid by agreeing to join Williams.

The news came as a massive shock to most people, but Wolff already knew that Hamilton was going to leave Mercedes after speaking with Sainz and his father on the phone.

In an interview with The Guardian, he said: "I wasn’t shocked at all. I knew this was happening a few weeks earlier when I got a phone call from Carlos Sainz and his father.

"He said: 'Something is cooking'. I said: 'Why would that happen before the start of the season?'. That same afternoon, I received calls from a few other drivers that were close to Charles Leclerc. Fernando Alonso too.

"I think it started from Leclerc knowing over the winter and then his closest allies hearing there was a seat free [at Mercedes]. I said to Susie: 'This is happening without us officially knowing'."

Wolff explained that he thought about calling Hamilton to ask if the rumours were true, but decided against it because he did not want to put the 39-year-old in a difficult position.

He said: "I did not want to put him in a situation where he had to lie to me because at that stage the contract wasn’t signed."

Hamilton, meanwhile, said earlier this year that he was 'terrified' about telling Wolff that he had agreed to join Ferrari.

"It’s been a rollercoaster of emotions from the moment I signed the contract," he told The Times. "Telling my boss, that was terrifying.

"But is so exciting because I remember as a kid watching Michael [Schumacher]. Every driver watches that car and you’re like, what would it be like to sit in the red cockpit?"