The 23-year-old France international has emerged as one of the Bundesliga's most highly regarded left-footed centre-backs, and his profile is understood to appeal to Barcelona's sporting department as they consider ways to strengthen their defence.
Lukeba has also made a change off the pitch, joining Excellence Sport, the agency that represents Barcelona defender Jules Koundé. The agency's representative recently met sporting director Deco in Barcelona, with Lukeba's potential availability among the subjects reportedly discussed.
A January transfer is considered unlikely, with RB Leipzig not prepared to sell the defender midway through the season. The financial picture could become more attractive next summer, when his reported release clause is due to fall from €80 million to €65 million.
That figure could still prove challenging for Barcelona, but the Catalans may have greater room to manoeuvre if they make significant sales during the summer window.
Lukeba's attributes make him an appealing option for a club looking to add a left-footed defender capable of contributing immediately. He is regarded as strong in duels, comfortable bringing the ball out from the back and effective in the air.
Barcelona have previously explored the possibility of signing him but opted against making a major investment in defence. Their need to strengthen that area may become more pressing if injuries continue to affect the squad.
The report suggests Lukeba would favour a move to Spain, with Barcelona an attractive destination, despite interest from several Premier League clubs. His salary is also considered more manageable than that of other high-profile defensive targets, including Inter's Alessandro Bastoni.
The club's summer planning could depend partly on departures. Ronald Araújo has been linked with Liverpool, while Alejandro Balde's future could also become a consideration, although a loan rather than a permanent transfer has been suggested for the latter.
Lukeba is not the only young left-footed centre-back on Barcelona's radar. Brazilian prospects Arthur Dias of Athletico Paranaense and Vitor Reis, currently at Manchester City, have also attracted attention, as has Ajax defender Youri Baas.
However, Lukeba is viewed as the more established option, with the potential to make an immediate contribution rather than requiring a longer period of development.
For now, Barcelona's priority is to identify a defender who could provide cover and competition during the second half of the season without requiring an excessive financial commitment. A significant January deal would likely depend on a major departure, making next summer the more realistic window for a move for Lukeba.