McLaren will open talks on their 2017 driver line-up at Monza as they prepare to decide whether Jenson Button or Stoffel Vandoorne will be Fernando Alonso's team-mate next season.

Although the team are widely expected to promote reserve driver Vandoorne at the expense of Button, McLaren are adamant that a decision has not yet been made.

The Italian GP weekend marks the start of Jost Capito's tenure as McLaren's new chief executive with consultations to determine McLaren's future line-up set to be at the top of his in-tray.

Although Capito's appointment was announced in January and he was in attendance for last week's Belgian GP, Capito will only officially begin work at McLaren on September 1.

Refuting reports that surfaced on race day at Spa that Button had been told by McLaren his contract would not be extended, chairman Ron Dennis told Sky F1: "We've always said that Monza would be when we discuss it internally. A final board decision will be taken at the end of September - that's the plan and it's always been the plan."

Johnny Herbert sits down with McLaren driver Jenson Button to review his season and look at his future in the sport Johnny Herbert sits down with McLaren driver Jenson Button to review his season and look at his future in the sport

Fernando Alonso, Button's current team-mate, enters the third and final year of his current deal with McLaren in 2017. Following an impressive drive from the back row to seventh at Spa, the Spaniard currently leads Button by 30 points to 17 in the Drivers' Championship.

Vandoorne, who stood in for the injured Alonso at Bahrain in April and then out-qualified Button before finishing in the points on his F1 debut, is regarded as one of the most talented drivers to emerge into the sport in recent years.

Mercedes boss Toto Wolff told reporters at Spa McLaren would be "crazy" not to promote Vandoorne and has called upon the sport to find a seat for the former GP2 champion.

"He's one that deserves a seat in Formula 1," said Wolff. "He has dominated GP2 in a way that was very special. He recovered from the reverse grid races on Sunday in a very special way and if guys like Stoffel don't come into Formula 1, the system is wrong."

Problem: Three into two seats won't go...

Dennis has previously hailed McLaren's all-champion pairing of Alonso and Button as "the best driver line-up in the sport". But the partnership of the 36-year-old Button and Alonso, 35, is also the oldest in F1 and while Vandoorne represents a more youthful alternative, he is already a relatively late newcomer to F1 at the age of 24.

"In some way it has it be [next year]," he told Sky Sports News HQ in July. "I've done all the preparation I could do - GP2, World Series, and now Super Formula. I've even done my first Grand Prix now.

"So, yes, 2017 I have to be on the grid."

Ahead of the summer break, McLaren chief Eric Boullier told Sky Sports: "What we won't do is hamper anyone's career. At the moment we have a young and aspiring driver, two tremendous world champions, and as and when we have to talk about it we will take everything into consideration."

Were Button to be dropped, his departure from McLaren would probably bring down the curtain on a 17-year career in F1. Although Williams have confirmed their interest in signing the 2009 world champion, the team's recent regression may persuade Button to hang up his gloves rather than return to the team with whom his F1 career started in 2000.