The 50-year-old has denied these accusations and is set to make his first public appearance since the ordeal began at the launch of the team’s 2024 car.
Horner had been to meet with the internal investigator hired by the team’s parent company, Red Bull GmbH, on Friday.
It is not known whether the team boss, who has been with the team since they debuted in the sport in 2005, will address the allegations in interviews at the RB20’s launch in Milton Keynes.
But there is no doubt that it will overshadow the event and will be the focus of attention in questions put to him and his drivers’ Max Verstappen and Sergio Perez.
The investigations are expected to continue for the next few weeks and it could potentially run past the first race of the season in Bahrain in March.
Pre-season testing will take place at the Bahrain International Circuit the week before, with the RB20 having already completed some laps in a shakedown session at Silverstone on Tuesday.