However, the Ligue 1 champs won't actively seek to sell the 19-year-old, according to Johnson.
Weah spent the second half of the 2018-19 season with Celtic. His loan was cut short ahead of preparations for this summer's Under-20 World Cup, and now his PSG future appears uncertain despite a bright, albeit limited, start to the campaign in France.
Thomas Tuchel is understood to be unconvinced by Weah, which prompted Eric Choupo-Moting's unexpected move to PSG last summer.
Europa League qualifiers Strasbourg are reportedly among a host of Ligue 1 sides monitoring Weah, while a return to Celtic also remains a possibility despite former manager Brendan Rodgers' move to Leicester City. Rodgers, and not Neil Lennon, was responsible for Weah's Celtic Park pilgrimage in January.
"Coming back to Celtic is definitely an option. The manager situation does not matter to me - it is more about the club and me feeling comfortable here," Weah told the Scottish Sun. "If you know you have the opportunity to develop and get game time, that is the most important thing at this stage."
According to reports, the first matters of importance for Tuchel and Co. this summer will be the potential departures of more prominent first-teamers Thomas Meunier, Layvin Kurzawa, and Christopher Nkunku.
Weah's father, George, is the current president of Liberia and the only African player to win the Ballon d'Or.