Fabrizio Romano reports that Köln's proposal has advanced quickly, with Moore himself viewing a move to Germany positively and a deal potentially wrapped up as soon as next week.
Borussia Dortmund and PSV Eindhoven had also been credited with interest and Middlesbrough were reported to be interested in a domestic loan too, but Köln have pulled clear of that competition and are now described as clear favourites.
Moore already holds a notable piece of Spurs history: he became the youngest player ever to appear for the club in the Premier League when he debuted at 16 years and 277 days old in May 2024, and later became Tottenham's youngest-ever scorer in major European competition, netting against IF Elfsborg in the Europa League at 17 years and 172 days.
Last season was spent on loan at Rangers in Scotland, where the England youth international scored seven goals and added four assists in 47 appearances across all competitions for the Ibrox club, having previously been part of the Tottenham squad that won the Europa League under Ange Postecoglou.
He is under contract at Tottenham until the summer of 2030, giving the club no urgency to sell outright, and a loan move keeps him within their long-term plans while providing senior football he might otherwise struggle to find in north London. Spurs have also been credited with interest in signing Cologne's own Said El Mala as a winger, a detail that helps explain why Moore's path forward at the club looks blocked for now, with manager Roberto De Zerbi also targeting multiple other wingers this summer, leaving little room even for a player of Moore's promise.
Moore has made no secret of his eventual ambition to establish himself in the Premier League, but regular minutes in one of Europe's top five leagues, wherever they come, are viewed internally as the priority for his development at this stage.