German Chancellor Angela Merkel is due to hold talks with Azerbaijani President Ilham Aliyev in Berlin on January 21.
The two leaders are expected discuss bilateral relations, energy policy and other issues when they meet in the German capital.
Human Rights Watch has urged Merkel to press Aliyev to free all jailed journalists, rights activists, and government critics, and stress there is a "direct link" between closer political and economic ties with Europe and the freeing of such individuals.
HRW said Azerbaijan jailed 34 government critics in 2014 and passed restrictive laws against independent groups and NGOs.
Khadija Ismayilova, an investigative journalist and contributor to RFE/RL, is being held in pretrial detention on suspicion of inciting a man to attempt suicide. Her supporters say the case is politically motivated.
RFE/RL's bureau in Baku was raided and shut down by the authorities in December.