Former Spain Under-21 international rejected a move to Atletico Madrid this summer to stay in Germany with Cologne.
The central defender joined the German club in an €8m deal from Sporting Gijon in 2017 and has impressed in the time since, despite the club being relegated from the Bundesliga in his debut campaign.
Mere had been a long-serving star of the Spain Under-21 side and had previously been linked to other leading Spanish clubs including Valencia and Sevilla.
“I know of the interest of different clubs,” Mere explained in an interview with the Teuton Bild newspaper, as cited by Diario AS.
The 22-year-old last season had a release clause of €10m but this tripled over the summer to €30m following Cologne’s return to the German top flight, having lifted last season’s second tier title.
Atletico Madrid oversaw a revolution of their defence this summer with Kieran Trippier, Renan Lodi, Mario Hermoso and Felipe Monteiro among the recruits following the exits of Juanfran Torres, Diego Godin and Filipe Luis over recent months.
