The 50-year-old Horner and former Spice Girls singer Halliwell looked poised as they made their way to Red Bull’s hospitality area, where they mingled with VIP guests in full view of photographers and television cameras.
Their appearance together at the season-opening race came after F1 media and key paddock figures received on Thursday an anonymous email containing a Google Drive link to purported evidence submitted to the investigation.
Recipients included the president of the sport’s governing body Mohammed Ben Sulayem and Formula 1 chief executive Stefano Domenicali as well as rival team bosses.
A lengthy investigation carried out by an independent lawyer for the championship-winning team's Austrian parent company, Red Bull GmbH, cleared Horner of the allegations on Wednesday.
Speaking on Thursday, after Horner was cleared but before the email was sent out, Mercedes and McLaren team bosses Toto Wolff and Zak Brown had called on Formula 1's governing body to push Red Bull for greater transparency about the investigation.
Ben Sulayem told the Financial Times that the controversy was damaging to the sport but that the body had no immediate plans to open its own investigation.
Horner met with Ben Sulayem and Domenicali in the paddock on Friday. The Briton is the sport’s longest-serving team boss having led Red Bull into Formula 1 in 2005.
Last year, he guided the Milton Keynes-based team to their sixth constructors’ title with 21 wins from 22 races in the most dominant campaign in the sport’s history.
