The player first arrived in London on a season-long loan from Atalanta in August 2021 and has since gone on to impress Italian boss Antonio Conte.
The Copa America winner has so far made 32 appearances for Tottenham and scored his first goal against Brighton last March.
Romero was an integral part of Conte's back three which helped Spurs to 10 victories from their final 14 Premier League games last season.
That run of results secured a top four finish and Champions League football, with the club set to take on Marseille, Eintracht Frankfurt and Sporting Lisbon in their group.
The 24-year-old featured in Tottenham's first two games of the new season against Southampton and Chelsea.
However, a groin injury ruled him out of action in recent games against Wolves and Nottingham Forest.
Nevertheless, his side are currently up to third in the table after winning three of their first four games.
Spurs face a testing schedule over the next few weeks as they take on West Ham and Fulham in back-to-back London derbies before kicking off their Champions League campaign against Marseille.
Conte's men will then face Manchester City, Sporting Lisbon and Leicester City.