The Bulgarian striker has been in fine form this season and his performances have reportedly attracted the attentions of Zenit St Petersburg, who were linked with Berbatov prior to his move from Manchester United to Craven Cottage.
Berbatov's agent Emil Danchev has indicated that the 32-year-old would consider a move to Russia, while insisting that the final decision rests in the hands of Fulham.
"I have heard of interest in Berbatov from Russian clubs in the past and I still hear of them today," Danchev told Izvestia.
"The Russian league is growing seriously and should soon become one of the leading championships in Europe so to play in that country would be interesting.
"Of course, much will depend on the decision of the Fulham hierarchy but, at the moment, I do not know of any formal offers."