Chelsea have reportedly been monitoring the defender for the past three months with scouts rumoured to have watched the Cameroon international in action last weekend, whilst Arsenal, Tottenham and AC Milan are also said to be interested.
N'kolou has reportedly agreed with the French outfit that he can leave in the summer if they receive an offer they are happy with, but he is not thinking about his future now.
He said: "I need to finish the season in a strong position, I am not thinking about any transfer at the moment."
The 22-year-old stated in December that he could not guarantee that he will be staying at Marseille in 2013 but insists his priorities currently remain with the Ligue 1 side.
N'Koulou added: "I want to help Marseille to finish with a trophy this season, my future will be discussed at the end of the season."