Max Verstappen has said he will park the idea of replacing Lewis Hamilton at Mercedes until later in the year.

Seven-time world champion Hamilton has agreed a one-year contract extension, but Mercedes are having to consider life after their star driver, who will be 37 next year.

On Thursday, the 95-time grand prix winner, who contracted Covid-19 in December, wrote on Instagram: "Emotionally and physically, this has been a challenging break. But the opportunity to get in the waves [surfing] has cleared my mind."

Verstappen, 23, is seen as the natural heir to Hamilton's Formula One throne, and although the Dutchman's current contract with Red Bull expires in 2023, a number of performance-related clauses could trigger his departure at the end of the season.

Verstappen's boss, Red Bull team principal Christian Horner, believes the Dutchman is top of Mercedes' wishlist.

"At the end of the day, I don't know what Lewis is going to do so I just focus on myself," said Verstappen.

"I am very focused on this year and making that a success. It is still very early in the season, so those kind of things I am not thinking about at this stage."

Verstappen and Hamilton in conversation during the 2020 season

Verstappen outperformed his Red Bull machinery to win two of the 17 races last year, including the season-concluding round in Abu Dhabi.

But he still finished third in the overall standings, behind Hamilton and his Mercedes team-mate Valtteri Bottas.

Following few rule changes, Mercedes are expected to remain the dominant force in 2021 ahead of a major overhaul of the sport's regulations next year.

Verstappen added: "We want to make it more difficult for Mercedes because they must be the favourites.

"We have made good steps with [engine supplier] Honda but the competition does not stand still so we have to wait and see if it is competitive enough to fight for wins.

"It is all looking promising but it makes no sense at the moment trying to hype it up.

"I am always very realistic and it makes no sense to talk about stuff now. We have to go to the first race in Bahrain and we will know if we have succeeded or not.

"I want to stay low-key and we should do the talking on the track, not next to the track. We know where we want to be, and where we want to get to, and that is what we have to now try to realise."

Testing for the new campaign gets under way in Bahrain on 12 March ahead of the curtain raiser, also in the Gulf Kingdom, a fortnight later.